What equipment is required for IFR flight according to FAR 91.205?

The correct answer highlights the essential equipment required for Instrument Flight Rules (IFR) operations as specified in the Federal Aviation Regulations (FAR) 91.205. According to this regulation, for IFR flight, an aircraft must be equipped with certain instruments and equipment to ensure safe operation in the absence of visual references.

The specified equipment includes a generator or alternator to provide electrical power, two-way radio communication equipment for communication with air traffic control, an altimeter for altitude measurement, and an attitude indicator to help the pilot maintain proper aircraft orientation in the three-dimensional space, particularly while flying in clouds or low visibility conditions.

These instruments are crucial for navigating, communicating, and ensuring the aircraft's operation under IFR conditions. The other answer choices do not fully satisfy the FAA requirements for IFR operations, as they incorporate equipment that is either not federally mandated for all IFR flights or is specific to particular types of operations or aircraft configurations. Thus, the answer reflects a solid comprehension of the regulations and the operating standards necessary for safety in IFR flight.