In the following passage some wordshave been deleted. Fill in the blanks with the help of the alternatives given.
Passage:

Most animals have their own habitats ..........(1) some make long journeys from one region to another. This ..........(2) called migration. It takes place at a particular ............(3) of the year. Birds are the best-known ............(4) but many other animals also migrate to places with ..............(5) climate.