A derived trait is a trait that the current organism has, but the previous one did not have.An ancestral trait is a trait that you, and your ancestors had.A vestigial structure is a structure that had some sort of use in your ancestor, but none in your current body
Answer:
The correct answer would be - complex eyes evolved in the gradual steps, each of which was fully functional and adaptive in improving visual acuity.
Explanation:
The natural selection of the complex traits such as the vertebrate eye (complex eye) are seems to be problematic, many biologist think that the complex eyes evolution is take place in gradual steps and each step of this evolution was adaptive and functional in improving the visual acuity.
The steps that were involved are like light sensitivity patch, a deepening hole or pit that help in sharp vision and many other random evolution steps.
Thus, the correct answer is- complex eyes evolved in the gradual steps, each step of this evolution was fully functional and adaptive that helps in improving visual acuity.