instruction:
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.
question:
Which statement best compares single-celled and multi-celled organisms?  
 (A) Tissues in a single-celled organism are like the cells in a multi-celled organism. (B) The nucleus in a single-celled organism is like the skin of a multi-celled organism. (C) Organelles in a single-celled organism are like the organs in a multi-celled organism. (D) The cytoplasm in a single-celled organism is like the nervous system in a multi-celled organism.
answer:
C


question:
A human CANNOT survive the loss of which of the following?  
 (A) The appendix (B) The liver (C) A lung (D) A kidney
answer:
B


question:
In 1783, Europe was unusually cold and foggy. The rain was acidic. Which event most likely caused the unusual climate in Europe that year?  
 (A) A logging company deforested millions of acres in South America. (B) A major earthquake and tsunami changed the path of the Gulf Stream. (C) A major volcanic eruption released ash and sulfur gas into the atmosphere. (D) An increase in the use of automobiles released more carbon dioxide into the atmosphere.
answer:

C