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: Hybridization is the practice of ____ different species interbreeding.\Question: Choose the right answer from options given a) no b) one c) two d) three

SOLUTION: c

PROBLEM: All spider mites have ____ legs and a lack of a separate head.\Question: Choose the right answer from options given a) eight b) four c) ten d) one

SOLUTION: a

PROBLEM: Samarium is the fifth most abundant of the rare elements and is almost ____ times as common as tin.\Question: Choose the right answer from options given a) two b) four c) three d) ten

SOLUTION:
b