What is the sexual structure produced by corn smut?

The sexual structure produced by corn smut, which is caused by the fungus Ustilago maydis, is indeed basidiospores from a basidiocarp. In the life cycle of this fungus, the basidiocarp represents the fruiting body that forms after the fusion of compatible haploid cells, eventually leading to the production of basidiospores. This reproductive strategy is characteristic of basidiomycetes, the group to which Ustilago maydis belongs. When conditions are favorable, these basidiospores are released into the environment, allowing the fungus to spread and infect new corn plants.

The other options do not accurately describe the reproductive structures associated with corn smut. An ascoma produces ascospores and is characteristic of ascomycetes, which is a different group of fungi altogether. Chlamydospores are asexual spores that serve for survival rather than reproduction and are not produced by Ustilago maydis. Oospores arise from the sexual reproduction of certain other fungi, particularly those in the Oomycete group, but they are not relevant to corn smut. Thus, the choice identifying basidiospores from a basidiocarp correctly aligns with