Differentiate the following activities on the basis of voluntary $(V)$ or involuntary $(IV)$ muscles:
$(a)$ Jumping of a frog
$(b)$ Pumping of the heart
$(c)$ Writing with hand
$(d)$ Movement of food in your intestine

(A) The classification of activities based on muscle type is as follows:
$(a)$ Jumping of a frog: This involves skeletal muscles which are under conscious control,hence it is Voluntary $(V)$.
$(b)$ Pumping of the heart: This is controlled by cardiac muscles which function automatically without conscious effort,hence it is Involuntary $(IV)$.
$(c)$ Writing with hand: This involves skeletal muscles controlled by the brain's conscious command,hence it is Voluntary $(V)$.
$(d)$ Movement of food in your intestine: This involves smooth muscles which perform peristalsis automatically,hence it is Involuntary $(IV)$.
Final Answer: $(a)-V, (b)-IV, (c)-V, (d)-IV$.