You will be given a definition of a task first, then some input of the task.
You are given a short paragraph, a question and two choices to answer from. Choose the correct answer based on the paragraph and write the answer(not the key).

Paragraph: 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.
 Question: African Americans have darker skin than other Americans. Researchers were not surprised to discover therefore, that vitamin D insufficiency among African Americans is _____ than among other Americans? 
 Choices: A)more prevalent 
B)less prevalent
Output:
more prevalent