Destination NAT purpose (Option C): Used to allow external hosts on the Internet to access internal/private resources (such as a web server in the DMZ). Destination NAT changes the destination IP of incoming traffic to match the internal server.
Pool-based NAT (Option D): SRX supports destination NAT pools, allowing multiple public IP addresses or ranges to be translated to internal servers.
Incorrect options:
Option A describes source NAT, not destination NAT.
Option B is incorrect because SRX does not support "interface-based" destination NAT.
Correct Statements: C and D

SRX devices operate on a default deny-all policy if no explicit match is found:
If a packet does not match any configured zone-based or global policy, it is implicitly denied.
The traffic is discarded silently by the default security policy (Option A).
Option B: No predefined "safe zone" exists.
Option C: Logging occurs only if explicitly configured; default deny does not automatically log traffic.
Option D: Incorrect, since the firewall defaults to deny, not permit.
Correct Behavior: Traffic is discarded by the default security policy.

Security policies can reference additional services and authentication behavior after traffic matches the policy criteria. SSL proxy is applied through a security policy by matching the traffic that should be decrypted and inspected, then referencing the SSL proxy profile as an application service. Firewall authentication is also policy-based; Juniper describes it as requiring users to authenticate to the SRX Series Firewall before access between zones and devices is permitted. Captive portal authentication is a web redirection mechanism and is not the direct security policy feature identified in this question. MAC bypass is not a standard SRX security policy service. Therefore, SSL proxy and firewall authentication are the two features applied through security policy processing.

To verify and demonstrate the effectiveness of content filtering on an SRX firewall, administrators use operational mode commands that display UTM statistics.
The command show security utm content-filtering statistics provides detailed counters showing how many connections were inspected, how many were blocked, and other related metrics.
This is the correct way to measure and demonstrate filtering effectiveness.
Commands in options A, B, and C provide status information for antispam, antivirus, and web filtering features, but they do not provide content filter effectiveness statistics.

The management functional zone on SRX devices is a special predefined zone with unique characteristics:
It is automatically created (Option C) and cannot be deleted.
It is used specifically for management-related traffic (Option A), such as SSH, Telnet, web management (J-Web), SNMP, and other control-plane services.
It does not contain revenue (data) interfaces (Option B is incorrect). Interfaces must be explicitly configured into user-defined zones.
The management zone can be referenced in policies if inter-zone communication involving management traffic is needed (Option D is incorrect).
Correct Statements: A and C