How will the tensions change if the whole setup starts accelerating in the upward direction?

Question

Two blocks A and B are tied with strings under water, as shown. The density of A is greater than water whereas that of B is less than water. The tensions in the strings are T1 and T2 respectively.

How will the tensions change if the whole setup starts accelerating in the upward direction?

AT1 increases and T2 decreases

BT2 increases and T1 decreases

CBoth increase

DBoth decrease

Select from the options above.

Correct Option: 3