Assertion: According to the law of conservation of mechanical energy, change in potential energy is equal and opposite to the change in kinetic energy.
Reason: Mechanical energy is not conserved.
Options:
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false and R is also false.