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").
Problem:Fact1: a cavern is formed by carbonic acid in groundwater seeping through rock and dissolving limestone, Fact2: When carbon dioxide is in water, it creates carbonic acid., Question: What forms caverns by seeping through rock and dissolving limestone? (A) pure oxygen (B) Something with a head, thorax, and abdomen (C) basic building blocks of life (D) carbon dioxide in groundwater (E) magma in groundwater (F) oxygen in groundwater (G) At the peak of a mountain (H) underground systems
Solution:
D