In an effort to reduce client-server latency transparent mode was enabled an SRX series device.

To answer this question, you need to know what transparent mode is and what types of traffic it permits. Transparent mode is a mode of operation for SRX Series devices that provides Layer 2 bridging capabilities with full security services. In transparent mode, the SRX Series device acts as a bridge between two network segments and inspects the packets without modifying the source or destination information in the IP packet header. The SRX Series device does not have an IP address in transparent mode, except for the management interface1. Therefore, the types of traffic that will be permitted in transparent mode are:

A. ARP (Address Resolution Protocol) traffic. ARP is a protocol that maps IP addresses to MAC addresses. ARP traffic is a type of Layer 2 traffic that does not require an IP address on the SRX Series device. ARP traffic is permitted in transparent mode to allow the SRX Series device to learn the MAC addresses of the hosts on the bridged network segments2.

B. Layer 2 non-IP multicast traffic. Layer 2 non-IP multicast traffic is a type of traffic that uses MAC addresses to send data to multiple destinations. Layer 2 non-IP multicast traffic does not require an IP address on the SRX Series device. Layer 2 non-IP multicast traffic is permitted in transparent mode to allow the SRX Series device to forward data to the appropriate destinations on the bridged network segments3.

The other options are incorrect because:

C. BGP (Border Gateway Protocol) traffic. BGP is a protocol that exchanges routing information between autonomous systems. BGP traffic is a type of Layer 3 traffic that requires an IP address on the SRX Series device. BGP traffic is not permitted in transparent mode, because the SRX Series device does not have an IP address in transparent mode, except for the management interface1.

D. IPsec (Internet Protocol Security) traffic. IPsec is a protocol that provides security and encryption for IP packets. IPsec traffic is a type of Layer 3 traffic that requires an IP address on the SRX Series device. IPsec traffic is not permitted in transparent mode, because the SRX Series device does not have an IP address in transparent mode, except for the management interface1.

References:

Transparent Mode Overview

ARP Support in Transparent Mode

Layer 2 Non-IP Multicast Traffic Support in Transparent Mode