Directions: In the following question, two statements are given with some words in bold. Which of the following pairs of bold words must be interchanged to make both sentences grammatically correct?

a. My mother's security(A) for Christmas is obvious(B) to anyone who sees the three thousand lights surrounding(C) our home.
b. The old man’s stern(D), fatherly gaze gave us a feeling of zest(E), despite the fact that he could barely rise(F) out of bed.