The leading cause of infertility in men is low sperm production, which affects their ability to conceive. Other listed conditions primarily affect women or are not direct causes of male infertility. Understanding these factors can help in diagnosing and addressing infertility issues. ;
The most likely explanation for Oliver's infertility is low sperm production, which is the leading cause of male infertility. Other options such as endometriosis and pelvic inflammatory disease relate to female reproductive health, while untreated gonorrhea, although relevant, is not the primary cause. Therefore, low sperm production is the best answer among the choices given.
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