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').

Japan is a highly urbanised country, with approximately ____ in every four people living in cities.\Question: Choose the right answer from options given a) ten b) no c) five d) three
d

Heme is made of ____ pyrrole groups united to form a porphyrin ring.\Question: Choose the right answer from options given a) five b) four c) eight d) six
b

Biology is a survey of the diversity of life, including all ____ King doms, viruses and prions.\Question: Choose the right answer from options given a) five b) two c) nine d) six

d