The workstation was configured with a static IP that is the same as the server is the most likely cause of the issue where users are unable to access any network resources. A static IP address is an IP address that is manually assigned to a device and does not change over time. A static IP address can be useful for devices that need to be easily identified or accessed on a network, such as servers or printers. However, if two devices on the same network have the same static IP address, it can cause an IP address conflict. An IP address conflict occurs when two devices try to use the same IP address at the same time, resulting in network communication errors or failures. An IP address conflict can prevent users from accessing any network resources that rely on the IP address for identification or routing. Reference: [CompTIA Network+ Certification Exam Objectives], What Is an IP Address Conflict? | HowStuffWorks

A site-to-site VPN is a type of VPN that connects two or more networks over the Internet using a secure tunnel. A site-to-site VPN allows users to access network resources on a laptop without logging in to the VPN application, as long as the laptop is connected to one of the networks in the VPN. A site-to-site VPN is transparent to the users and does not require any additional software or configuration on the client devices.

Power over Ethernet (PoE) is a technology that allows network-connected devices to receive power over the same Ethernet cables that are used for data transfer. PoE is commonly used to power devices such as VoIP phones and cameras, making it an ideal choice for network administrators looking for a cost-effective solution. PoE is not typically used for other devices such as printers, cable modems, laptops, and UPSs.

A VLAN (Virtual Local Area Network) is a logical grouping of devices that share the same broadcast domain, regardless of their physical location or connection. VLANs can improve network performance, security, and management by separating different types of traffic, such as data, voice, and video1.
A VoIP (Voice over Internet Protocol) phone is a device that uses the Internet to transmit voice calls, instead of the traditional phone lines. VoIP phones require a network connection, an IP address, and a gateway to communicate with other VoIP devices or phone systems2.
A DHCP (Dynamic Host Configuration Protocol) server is a device that automatically assigns IP addresses and other network configuration parameters to devices that request them. DHCP simplifies network administration and avoids IP conflicts3.
A switchport is a physical interface on a switch that connects to a network device, such as a VoIP phone, a computer, or another switch. A switchport can be configured to belong to a specific VLAN or to carry traffic from multiple VLANs4.
A gateway is a device that connects different networks and enables communication between them. A gateway can also perform protocol conversion, such as translating between VoIP and analog signals5.
A route is a path that a packet takes to reach its destination. A route consists of a destination network, a next-hop device, and a metric. A router is a device that forwards packets based on their destination IP addresses and the routing table.
In order to allow a newly installed VoIP phone to operate correctly, the network administrator needs to assign the phone's switchport to the correct VLAN. This will ensure that the phone can communicate with the DHCP server and obtain an IP address that belongs to the same network as the phone system. This will also isolate the voice traffic from the data traffic and improve the quality of service.
Statically assigning the phone's gateway address is not enough to allow the phone to operate correctly, as the phone still needs an IP address and a subnet mask to communicate with other devices on the network. Moreover, statically assigning network parameters can be tedious and prone to errors, especially for a large number of devices.
Configuring a route on the VoIP network router is not necessary to allow the phone to operate correctly, as the phone and the phone system are on the same network and do not need to cross any routers. Configuring a route would only be needed if the phone and the phone system were on different networks and needed to communicate through a router.
Implementing a VoIP gateway is not required to allow the phone to operate correctly, as the phone and the phone system are both VoIP devices and use the same protocol. Implementing a VoIP gateway would only be needed if the phone or the phone system needed to communicate with a non-VoIP device or system, such as a traditional phone line or a public switched telephone network (PSTN).
Reference:
1: VLAN
2: VoIP Phone
3: DHCP
4: Switchport
5: Gateway
6: [Route]
7: [VoIP VLAN Configuration]
8: [Static vs Dynamic IP Addressing]
9: [Routing Basics]
10: [VoIP Gateway]

An on-path attack (also known as a man-in-the-middle attack) is a type of security attack where the attacker places themselves between two devices (often a web browser and a web server) and intercepts or modifies communications between the two1. The attacker can then collect information as well as impersonate either of the two agents. For example, an on-path attacker could capture login credentials, redirect traffic to malicious sites, or inject malware into legitimate web pages.
The other options are not correct because they describe different types of attacks:
* IP spoofing is the practice of forging the source IP address of a packet to make it appear as if it came from a trusted or authorized source2.
* VLAN hopping is a technique that allows an attacker to access a VLAN that they are not authorized to access by sending packets with a modified VLAN tag3.
* Rogue DHCP is a scenario where an unauthorized DHCP server offers IP configuration parameters to clients on a network, potentially causing network disruption or redirection to malicious sites4.
Reference
2: Understanding Targeted Attacks: What is a Targeted Attack?
3: Types of attacks - Security on the web | MDN
1: What is an on-path attacker? | Cloudflare
4: [What is a Rogue DHCP Server? - Definition from Techopedia]