Question

look at the diagram of the solar system. what observation did this geocentric model of the solar system help to explain? orbit speed the phases of venus retrograde motion the rising of the sun

Explanation:

The geocentric model used epicycles to explain the apparent retrograde motion of the planets. Retrograde motion is when a planet appears to move backward in the sky from our perspective on Earth. The other options like orbit speed, phases of Venus, and the rising of the Sun are better - explained by the heliocentric model.

Answer:

retrograde motion