According to embryology, which three species have the closest common ancestor? insects, birds, and fish
amphibians, mammals, and birds
reptiles, amphibians, and bacteria
insects, bacteria, and reptiles

Option- (B): Amphibians, mammals, and birds.

Explanation:

Common Ancestry linkage

As amphibians were the first to evolve and develop themselves as a more complex form of life. While the mammals and birds are said to be evolved from the amphibians, as both them they covers there embryos inside a sheet or a specific protected layer around there embryo. Which terms them as amniotes.