Which bird with a distinctive call lays its eggs in the nests of other birds?

A. Cuckoo
B. Sparrow
C. Parrot
D. Humming bird

The European Cuckoo, whose distinctive call is immortalized in the sound of the “cuckoo clock,” is the bird in which this habit has been most thoroughly studied. Female European Cuckoos lay their eggs only in the nests of other species of birds.