Answer: Option (A) is the correct answer.
Step-by-step explanation:
A chemical reaction where heat energy is absorbed by the reactant molecules is known as an endothermic reaction.
For example,

The value of
= +ve for an endothermic reaction.
On the other hand, a chemical reaction in which heat energy is released by the reactant molecules is known as an exothermic reaction.
For example,
is an exothermic reaction.
As 200 kJ of heat was taken in on average by the calorimeter so, it means heat energy is absorbed by the calorimeter.
Thus, we can conclude that the given reaction is endothermic in nature.