One of the "nails in the coffin" for earth-centered universe was

Answer

The right option of this question is Galileo's observation of stars in the Milky Way.

Explanation

The two types of models and the geocentric model and heliocentric model during the ancient time. In the first model, it was considered that all heavy bodies rotate around the sun. In the second model, it was stated that all heavy bodies rotate around the sun. in his time, Gallio supported the second model as the sun is the central part and around it, all other heavy bodies rotate. He was the first person, who used the telescope to observe dark spot and the Venus movement which then supported the heliocentric model.