In this task, you are given a question and answer for that. The answer will fill in the blank or will complete the unfinished question. Your task is to provide an explanation based on the given question or fill-in-the-blank statement, and answer.

Example Input: Question: If an animal is able to eat food more difficult is it more or less likely to reproduce? 
 Answer: less
Example Output: Natural selection is the process by which living things with beneficial traits produce more offspring, so their traits become more common over time.

Example Input: Question: When there are fewer people in an area the amount of water will 
 Answer: increase
Example Output: The availability of water is projected to get worse as demand increases.

Example Input: Question: Two friends are headed to the beach, Mike and John. Mike is white, and John is black. Both want to make the same amount of vitamin D through sun exposure. The person who will take longer to make the amount of vitamin D is 
 Answer: John
Example Output:
Pigments in the skin act like a filter that can prevent the skin from making vitamin D. As a result, people with darker skin need more time in the sun than people with lighter skin to make the same amount of vitamin D.