請依下文回答第 41 題至第 45 題 All birds have voices. We think of them 41 singing, but many, such as birds of prey and ostriches, do not do
so. In spite of this, they have a language that includes a variety of sounds, each 42 its own particular meaning.
The songs that we hear from songbirds in the spring are often complicated, 43 they are saying something
simple. Usually the singers are the males. They often sing at the edge of their territory. In this way, they attract mates
and inform other males that this area 44 them. The songs are 45 ; however, they do save real fighting.
【題組】44
(A) accounts for
(B) depends on
(C) increases with
(D) belongs to