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').

Marriage is the legal union of ____ people.\Question: Choose the right answer from options given a) one b) no c) five d) two
d

Condors become sexually mature at about five or ____ years of age and mate for life.\Question: Choose the right answer from options given a) nine b) seven c) one d) six
d

Domestic dogs have ____ lower, but only two upper molars.\Question: Choose the right answer from options given a) one b) three c) four d) zero

b