You will be given a definition of a task first, then some input of the task.
You are given a science question (hard-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

In 2005, a team of scientists discovered a photosynthetic bacteria living near the molten lava of a thermal vent ecosystem deep in the Pacific Ocean. The bacteria lived 2400 meters below the surface of the ocean, yet made energy from photosynthesis. Which conclusion best explains the results?
(A) Photosynthesis can occur without light. (B) The hydrothermal vent emits usable light. (C) High water pressure can power photosynthesis. (D) The bacteria used to live at the ocean's surface.
Output:
B