Answer: The correct option is (A) 13xy.
Step-by-step explanation: We are given to select the greatest common factor (G.C.F) of the following two expressions :

The G.C.F. of two numbers is the product of the common terms in the prime factorization of the expressions.
We have

Therefore, the G.C.F. of the given expressions will be

Thus, the required G.C.F is 13xy.
Option (A) is CORRECT.