Final answer:
An APU OIL PRESSURE LOW condition is indicated on the EICAS system, which is critical for monitoring engine and aircraft system information.
Step-by-step explanation:
An APU OIL PRESSURE LOW condition will be indicated on the EICAS (Engine Indicating and Crew Alerting System). The EICAS is a system used in modern aircraft to display engine and other aircraft system information to the flight crew. This centralized system helps in monitoring engine performance, aircraft system status, and alerts the crew to various conditions, such as an APU oil pressure drop. The HUD (Head-Up Display), MFD (Multi-Function Display), and EFB (Electronic Flight Bag) serve different primary functions, and they are not typically used to display this type of warning. The HUD is used to project essential information onto a transparent display in the pilot's forward field of view, the MFD is used to display various navigational and situational information, and the EFB is an electronic information management device that helps flight crews perform flight management tasks more easily and efficiently.