Option D.
Assuming 232 is divisible by some number x.
Now, 296 + 1
= (232)3 + 1
= (232)3 + 13
= (232 + 1) ((232)2 - 232 + 1) [(x3 + y3) = (x+1)(x2 - xy +1)]
Look at the first (232 + 1), it is divisible by x as established. This the Fourth is completely divisible.