The correct answer is antheridium.
An antheridium is a haploid organ which produces and contains male gametes called antherozoids or sperm. It consists of sterile cells (support and protective structure) and spermatogenous tissue which gives rise to spermatids via mitotic cell division. In some bryophytes, the antheridium is located on the apex of an antheridiophore, a stalk-like structure.