Given a sentence with a missing word, pick the answer option that best fills out the missing word in the sentence. Indicate each answer with its index ('a', 'b', 'c', 'd').

Example Input: Tropical trees can be rampant growers, and can outgrow a wiring in as little as ____ days' time.\Question: Choose the right answer from options given a) four b) eight c) six d) ten
Example Output: d

Example Input: China has about ____ in four of all smokers in the world.\Question: Choose the right answer from options given a) one b) seven c) ten d) six
Example Output: a

Example Input: Some legends have ____ trees holding the sky at the corners of the world.\Question: Choose the right answer from options given a) three b) seven c) four d) eight
Example Output:
c