(A) "carry off" (III) → means to accomplish/handle something successfully with skill, fits perfectly with successfully handling responsibilities.
(B) "carry through" (IV) → means to complete or implement something fully, ideal for executing all policies.
(C) "come about" (I) → means to happen or occur, appropriate for asking how the loss happened.
(D) "come across" (II) → means to meet or encounter by chance, perfect for running into old friends at a reunion.
Hence, Option 2: (A) - (III), (B) - (IV), (C) - (I), (D) - (II) → Each phrasal verb matches its sentence contextually: carry off for successfully accomplishing responsibilities, carry through for implementing policies, come about for how something happened, and come across for encountering people → correct