Which buttons remain functional during an EICAS Control Panel failure?

In the context of the EICAS (Engine Indication and Crew Alerting System) Control Panel on the CRJ, understanding the functional status of various buttons during a control panel failure is crucial for pilot response and aircraft operation.

The buttons that remain functional during an EICAS Control Panel failure include PRI (Primary), CAS (Crew Alerting System), STAT (Status), and STEP. These buttons serve specific purposes that are vital to crew awareness and decision-making during abnormal situations.

PRI provides the main engine indications, which are critical for monitoring engine performance. CAS activates alerts to inform the crew about various system statuses, ensuring that the pilots are aware of any operational issues. STAT presents a summary of the aircraft's status, allowing pilots to quickly assess overall system health. STEP facilitates the progression through different pages of the EICAS display, providing the capability to access further information without compromising situational awareness.

With this understanding, it's clear why the selection that includes PRI, CAS, STAT, and STEP is the correct answer, as each of these buttons plays an essential role in maintaining operational oversight even if one control panel encounters failure. The other options include combinations that introduce buttons not operational during such a failure, making them less appropriate in this scenario.