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').

Quarks also come in ____ 'colours', terms for a property a little like electrical charge.\Question: Choose the right answer from options given a) three b) nine c) six d) no
a

Most women take about ____ weeks to stop bleeding and to heal inside.\Question: Choose the right answer from options given a) two b) no c) four d) zero
c

Centre of mass is where the ____ lines cross.\Question: Choose the right answer from options given a) nine b) zero c) two d) three

c