Explanation
The session table is a limited resource for SRX Series devices. If the session table is full, any new sessions will be rejected by the device. The aggressive session-aging mechanism accelerates the session timeout process when the number of sessions in the session table exceeds the specified high-watermark threshold. This mechanism minimizes the likelihood that the SRX Series devices will reject new sessions when the session table becomes full1. To perform aggressive session aging, you need to configure the following parameters1:
early-ageout -During aggressive session aging, the sessions with an age-out time lower than the early-ageout threshold are marked as invalid. The early-ageout configuration specifies the timeout value, in seconds, that will be applied once the high-watermark value is met. For example, if you set the early-ageout to 30 seconds, any session that has been inactive for at least 30 seconds will be aged out when the high-watermark is reached2.
high-watermark -The device performs aggressive session aging when the number of sessions in the session table exceeds the high-watermark threshold. The high-watermark configuration specifies the percentage of how much of the session table can be allocated before applying a more aggressive age-out timer. For example, if you set the high-watermark to 90 percent, the device will start aging out sessions more aggressively when the session table reaches 90 percent of its capacity3.
Therefore, the correct statements are B and D.
References: Understanding Aggressive Session Aging high-watermark early-ageout

Encrypted traffic insights (ETI) uses domain names to notify SRX Series devices about known malware sites. ETI is a feature of the SRX Series firewall that can detect and block malware that is hidden in encrypted traffic. It works by analyzing the domain names of the websites that the encrypted traffic is attempting to access. If the domain name matches a known malware site, ETI will send an alert to the SRX Series device, which can then take appropriate action to block the traffic. ETI is a useful tool for protecting against threats that attempt to evade detection by hiding in encrypted traffic.