HUMMINGBIRDS ARE THE ONLY BIRDS CAPABLE TO FLY BACKWARD AS WELL AS...

90. - 2000 CAU TRAC NGHIEM ANH A B C
2000 CAU TRAC NGHIEM ANH A B C

90. Hummingbirds are the only birds capable to fly backward as well as forward,

up, and down.

a. the only birds

b. to fly

c. as well as

d. forward

-> b