Answer with explanation:
A motion is said to be Simple Harmonic motion if it is to and fro motion that is a type of periodic motion where motion of an object repeats after certain interval of time.
Option A:→ A police car shining a spotlight into buildings as it drives by is not a periodic motion because when a car is moving towards a spotlight does not repeat in a small duration.
Option B:→ Calculation of Angle of Elevation for a Building is not Simple Harmonic as it is not Periodic.
Option C:→ The motion of a piston is simple harmonic because when engine is in motion the piston moves up and down that is a Periodic motion.This motion is also called reciprocating motion as it is not completely periodic which can be converted into circular motion with the help of an Instrument called Crankshaft.
Option D: →A ball bouncing on a sidewalk is Parabolic of different Latus rectums .It's distance from base that is maximum height attained by ball starts decreasing when friction comes into play and stops when Inertia stops acting on the ball.
Option C:→ The motion of a piston is an example of simple harmonic motion.