Definition: In this task, you are given a multiple-choice question and you have to pick the correct option. Answer with option indexes (i.e., "A", "B", "C", and "D").
Input: A micro-scratch test is able to determine which rock formations deep inside the earth's sub-surface are the hardest and how resistant the formations are to being (A) scratched, fractured or otherwise deformed (B) transformed into different minerals (C) melted and otherwise liquified (D) scratched with ice breakers
Output:
A