Detailed Instructions: 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").
Q: Fact1: being exposed to wind can cause erosion of soil, Fact2: Wind erosion is slowed by wind barriers such as trees and shrubs., Question: what blocks erosion? (A) roots (B) Raft (C) bamboo (D) trees (E) bushes (F) Roads (G) rivers (H) streams
A:
D