The correct answer is D. 5,400rpm HDD.
A 5,400rpm HDD (Hard Disk Drive) is a type of storage device that uses spinning magnetic disks to store dat a. A 5,400rpm HDD is the least expensive per gigabyte among the options given, as it has a lower rotational speed and performance than other types of HDDs or SSDs (Solid State Drives). A 5,400rpm HDD is suitable for archiving a large number of photos that are not accessed frequently, as it can offer high capacity and reliability at a low cost.
the average cost per gigabyte of a 5,400rpm HDD is around $0.02 to $0.0312, while the average cost per gigabyte of the other options are:
NVMe SSD: $0.10 to $0.1534
SCSI RAID: $0.20 to $0.305
15,000rpm SAS: $0.30 to $0.40
Therefore, a 5,400rpm HDD is the cheapest option among the four.

Thunderbolt 3 is a USB-C port, so any device with a USB-C connector can be plugged into it. MiniUSB, microUSB and USB-A are not compatible with Thunderbolt 3.

Explanation
RAID 0 is a disk array configuration that splits data across two or more disks without parity or mirroring.
RAID 0 provides the best I/O performance because it allows parallel read and write operations on multiple disks. RAID 0 also provides the most storage capacity possible because it does not use any disk space for redundancy. However, RAID 0 does not provide any fault tolerance and increases the risk of data loss if any disk fails.
References: The Official CompTIA A+ Core 1 Student Guide (Exam 220-1101) eBook, page 252

Explanation
Telnet is an unsecure remote access protocol that allows a user to connect to a remote device and execute commands on it12. Telnet does not encrypt the data that is transmitted between the user and the device, which means that anyone who intercepts the network traffic can read the information, including usernames and passwords12. Telnet also does not authenticate the user or the device, which means that anyone can impersonate either party and gain unauthorized access1.

RAID 0 is a disk array configuration that splits data across two or more disks without parity or mirroring.
RAID 0 provides the best I/O performance because it allows parallel read and write operations on multiple disks. RAID 0 also provides the most storage capacity possible because it does not use any disk space for redundancy. However, RAID 0 does not provide any fault tolerance and increases the risk of data loss if any disk fails.
References: The Official CompTIA A+ Core 1 Student Guide (Exam 220-1101) eBook, page 252