While Having a Discussion, Technician a Says That the Automotive

While having a discussion, Technician A says that the Automotive Engine Rebuilders Association recommends prefilling hydraulic lifters. Technician B says that if they are underfilled, the valves can be held off their seats, which will make starting the engine difficult. Who is correct?

A) A only
B) B only
C) Both A and B
D) Neither A nor B