Explanation :
The mechanical energy is the sum of the potential energy and the kinetic energy i.e.
ME = PE + KE
Kinetic energy is due to the motion of an object.
Potential energy is possessed by an object due to its height under the action of gravity.
Mathematically, it is written as :
PE =mgh
Where
m is the mass of the object
g is acceleration due to gravity
h is the height relative to reference level.
So, an object's gravitational potential energy is NOT related to its speed.
Hence, the correct option is (c) 'Its speed'.
