As we know sperms lack a great part of the cellular organs as they are totally reduced, even more, the DNA is super compacted, therefore we cannot consider the Endoplasmatic reticulum as a cause nor lysosomes as both are lacking in it, perhaps this could be attributed to the spermatids in the testis nonetheless this would be due to development and maturation and other mutations would be involved, so the most likely due to the inability to swim would be a problem in the flagella, proteins or mitochondria, so the correct answer is the second option.