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').

Mechanical digestion occurs as ____ strong layers of muscle contract to produce a churning motion.\Question: Choose the right answer from options given a) four b) no c) three d) six
c

Cattle are the second most important commodity in ____ states and third in six states.\Question: Choose the right answer from options given a) nine b) five c) no d) eight
a

All female kangaroos have a well-developed pouch that opens forward and contains ____ teats.\Question: Choose the right answer from options given a) one b) no c) four d) ten

c