In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").

Fact1: the color of leaves on deciduous trees usually changes in the autumn season, Fact2: Many broad-leaved trees are deciduous., Question: On many broad-leaved trees, what usually changes in the autumn season? (A) colors of the spectrum (B) chemical changes (C) color of branches (D) color of leaves (E) temperature (F) shape of branches (G) size of needles (H) bloom time
D