TASK DEFINITION: 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').
PROBLEM: Ruminants have an even number of toes on each foot and a stomach with either three or ____ chambers.\Question: Choose the right answer from options given a) four b) two c) seven d) five

SOLUTION: a

PROBLEM: Female bilbies have a backward-opening pouch with ____ nipples.\Question: Choose the right answer from options given a) no b) two c) five d) eight

SOLUTION: d

PROBLEM: Secondary aluminum uses ____ percent of the energy required to produce primary aluminum.\Question: Choose the right answer from options given a) ten b) five c) nine d) eight

SOLUTION:
b