Final answer:
Cats are the main hosts for Toxoplasma gondii during its life cycle.
Step-by-step explanation:
The main hosts for Toxoplasma gondii during its life cycle are cats. Domestic cats are the definitive hosts for the sexual stages of the parasite and are the main reservoirs of infection. Cats shed T. gondii oocysts in their feces, which can spread to humans through contact with fecal matter on cats' bodies or in litter boxes.