Which actions shall be taken if the rotor RPM indicator fails during cruise flight?

Question

Question PPL(H) - Private Pilot License - Aircraft General Knowledge

QuizVDS · Accepted Answer

Continue the flight as long as the engine RPM indicator works

QuizVDS · Answer

Try to get back an indication by opening and closing the throttle

QuizVDS · Answer

Increase engine power and continue the flight to the nearest airfield

QuizVDS · Answer

Perform an emergency landing on suitable terrain

Id 173 - PPL(H) EN - Which actions shall be taken if the rotor RPM indicator fails during cruise flight?