Which of the following instruments is not s present on the flight deck of a light training airplane like Cessna-152?

Basic training aircraft like the Cessna-152 are manually flown and do not have autopilot systems to keep costs low and teach fundamental flying skills. The other instruments listed (VSI, altimeter, airspeed indicator) are essential flight instruments present on all aircraft including trainers. Autopilot is found on more advanced or complex aircraft.