Which are classified as sac fungi?

Sac fungi belong to the group Ascomycota, which includes truffles, morels, and yeasts. Mushrooms and puffballs are generally basidiomycetes, while rusts are also basidiomycetes and chytrids belong to a separate fungal group. Therefore, the set containing only sac fungi is truffles, morels, and yeast.

AI-written and checked against the verified answer.