Assertion: when calcium carbonate is heated.it decomposes to give calcium oxide and carbon dioxide
reason: the decomposition reaction takes place on application of heat . therefore it is an endothermic reaction ​

A)Both A and R are true, and R is the correct explanation for A.

B)Both A and R are true, and R is not the correct explanation for A.

C) A is true but R is false.

D) A is false but R is true.