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: Trees have woody stems covered with bark., Fact2: Bark on mature trees runs 6 to 12 inches thick, insulating the tree against fire damage., Question: What do trees have that insulates? (A) hats (B) looseness (C) dogs (D) woody stems (E) food and shelter (F) cells (G) storing water (H) In their leaves
D