Which constellation in the zodiac is associated with Apollo and Heracles, Iasion and Triptolemus, or Castor and Pollux?

The constellation associated with Apollo and Heracles, Iasion and Triptolemus, or Castor and Pollux is Gemini. In mythology, Gemini is linked to the twin brothers Castor and Pollux, who are known for their close bond and shared adventures. Apollo, although primarily associated with other symbols, is also linked with the twin's lineage, as they are often regarded as sons of Leda, connecting them to the Olympian gods. Heracles and Iasion are connected to fertility and agriculture, which also ties into the themes presented in the mythology surrounding Gemini.

Each of the other options does not have this direct linkage to the mythological figures mentioned. Taurus, for example, is typically associated with the bull and the myth of Zeus and Europa. Aquarius represents Ganymede, the water bearer, while Leo is symbolized by the Nemean Lion, which is significant in Heracles' labors but is not directly related to the twins or the pairings mentioned in the question. Therefore, Gemini stands out as the correct association due to its focus on these key mythological figures.