According to embryology, why do fish and birds have a common ancestor?

They both have embryos with gill slits and tails.
They both have embryos with traits that eventually disappear.
They both have embryos that develop into adults.
They both have embryos that form from a fertilized egg.

can you give me more to work here with plzs and you

the water is warmed up by the sun and then it evaporates into the atmosphere. the sunlight warms the water by its heat. water is then cooled down and condensation takes place. the water then finally returns back to the earth by the process of precipitation in the form of rain or ice.

explanation: