Which of these characteristics is common only at the embryonic stage of fish and humans, and is suggestive of a common ancestor between the two? A) presence of lungs B) presence of a tail C) presence of gill slits D) presence of a vertebral column

it is c) presence of gill slits

C.)

Explanation:

All vertebrates have a vertebral column. Lungs are present only in humans. A tail, though not fully developed, exists in humans in the adult stage too. The presence of gill slits at the embryonic stage of both groups suggests an ancient common ancestor.