Select the word from the list that best fits the definition early greeks a. heliocentric b. geocentric

The answer is B. Geocentric

Option B i.e Geocentric is the correct answer.

The early Greeks believed that planets followed perfect circular orbits around the Earth and this came to be known as Geocentric Modal/Theory of solar system.  Plato and later Heraclides (330 B.C.) advocated the same.  After that we see Aristarchus (270 B.C.) proposed that Sun is the center of solar system and earth and other planets move around its orbit. This came to be called Heliocentric theory of solar system.