Given the task definition and input, reply with output. 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: boiling means change from a liquid into a gas by adding heat energy, Fact2: Water is heated to the boiling point and changes to steam., Question: What does water turn into after boiling? (A) gas (B) Dew (C) lake (D) solid (E) oxygen (F) liquid (G) oil (H) salt
A