Question

A speed-time (v-t) graph of an object is shown in the figure.

Answer 1

The answer is C.

If the object was dropped or thrown through "air", the air-resistance will slow down the speed of the object resulting into a curved line. This eliminates options B and D.

Refer the following link below for the graphs in case of options A (i.e., dropped through vacuum) and B (dropped through air).

https://physics.stackexchange.com/questions/104368/free-falling-object-with-air-resistance

If the object was "dropped", the initial speed would be zero that eliminates option A.