Q.Among the reptiles, which one is the exception in having a completely four-chambered heart like the birds and mammals?

Chiefly terrestrial, crawling/creeping vertebrates with dry, cornified skin covered by scales or scutes, an adaptation limiting water loss on land. The heart is typically three-chambered, with crocodilians as a notable four-chambered exception. Fertilisation is internal, and the fertilised egg is enclosed in a protective, calcareous-shelled amniotic egg laid on land, giving direct development with no aquat …