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: Potassium helps maintain fluid regulation and normal pH. All ____ help normalize.\Question: Choose the right answer from options given a) three b) six c) two d) one

SOLUTION: a

PROBLEM: Most linguists organize the African languages into ____ major language families.\Question: Choose the right answer from options given a) three b) four c) eight d) no

SOLUTION: b

PROBLEM: Evolution occurs in ____ ways, mutation and natural selection.\Question: Choose the right answer from options given a) five b) two c) eight d) no

SOLUTION:
b