The correct answer is C. Warner, Home.
A multiple aspect signal is a railway signal that uses more than one aspect (position of the signal arm or aspect of the light) to indicate the permissible speed and direction of movement.
In multiple aspect signalling, the least number of signals that need to be installed on a C class station is a home signal and a warner signal. The home signal indicates the permissible speed and direction of movement for trains approaching the station, while the warner signal indicates that the train is approaching the home signal.
The distant signal, starter signal, and outer signal are not required on a C class station. The distant signal is used to warn trains of the approach of the home signal, while the starter signal is used to control the entry of trains into the station. The outer signal is used to warn trains of the approach of the distant signal.
C class stations are small stations with a low volume of traffic. They are typically located in rural areas or on branch lines.