Given below are two statements, one labelled as Assertion A and the other labelled as Reason R.Assertion A: In 1979 China waged a punitive war against Vietnam which resulted in huge casualties on both sides.Reason R: This was because of their rivalry of interests in Cambodia. Vietnamese troops occupied Cambodia to eliminate the Pol Pot regime that had Chinese support.Codes:

• 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 not false.
• D. A is false but R is true.