13. Consider a divide-and-conquer algorithm, which solves a problem of size n by dividing it into two subproblems of size n/3 and n/5, respectively. The solutions of the subproblems are then combined in θ(n2) time. Which of the following is correct about the time complexity T(n) of this algorithm? (A) T(n) must be in θ(n2). (B) T(n) must be in O(n2) but not nec ssarily in Ω(n2). (C) T(n) must be in Ω(n2) but not necessarily in O(n2). (D)None of the above. The complexity of T(n) depends on the exact valuc of n.