Question

unusual bird parenting
birds have a reputation as excellent parents. they expend a great deal of effort in building nests in which to lay their eggs. they patiently incubate the eggs, keeping them warm and safe until they hatch. birds also bring food to their newly hatched offspring until the baby birds are independent. however, some unusual birds, known as brood parasites, dont provide any parental care for their young. perhaps the most famous brood parasite is the cuckoo. instead of building a nest, the cuckoo lays her eggs in the nest of another species with similar - looking eggs. the female cuckoo simply removes an egg laid by the host female, lays her own egg, and then leaves, expecting the host bird to care for the imposter.
what is the main, or central, idea of the passage?
unlike most species of birds, brood parasites such as the cuckoo dont provide any parental care.
unlike most species of birds, brood parasites such as the cuckoo dont build nests.
most birds build nests for their young, incubate the eggs, and are generally devoted parents.

Explanation:

The passage first describes how most birds are excellent parents (building nests, incubating eggs, feeding offspring). Then it introduces brood parasites (like cuckoos) that don't provide parental care, explaining the cuckoo's behavior of laying eggs in other nests. The first option captures the contrast between most birds and brood parasites regarding parental care, while the second focuses only on nest - building (a part of parental care) and the third only on typical bird parenting without addressing the unusual case.

Answer:

Unlike most species of birds, brood parasites such as the cuckoo don't provide any parental care.