In the following three passages, some of the words have been left out. First read the passage over and try to understand what it is about. Then fill in the blanks with the help of the alternatives given.
Passage II:

The wings of some birds are so small that they are 56 for flying. Earlier such birds 57 fly. But after living for thousands of 58 in places where they had no 59 there was no need for them to fly, and they  60 on the ground. After a while their 61 ones could no longer rise into the air. The ostrich, rhea, emu and cassowary 62 fly, but they can run fast on their long, strong legs. Ostriches  63  in Africa and are found on the grassy places 64 they live along with big groups of zebras. The rhea looks like the ostrich, 65 it is smaller and has three toes on each feet, while the ostrich has only two.