What is a plasmid? (gradpoint)

a. a type of dna polymerase
b. a large bacterial chromosome
c. a small ring of bacterial dna
d. a restriction endonuclease

The embryos of a bird, a reptile, and a mammal are similar in appearance. how does comparing the physical appearance of embryos of different species support the theory of evolution? a. it shows that these organisms share a common ancestor. b. it provides evidence that these organisms eat the same foods.c. it shows that these organisms share the same habitat.d. it provides evidence that these organisms suffered a genetic mutation.