Which of the following best describes a physiological function of testosterone in the male reproductive system?

• AMaintenance of spermatogenesis and development/maintenance of male secondary sexual characteristics
• BDirect secretion of androgen-binding protein by Sertoli cells without needing testosterone itself
• CSelective negative feedback that suppresses only LH from the anterior pituitary while sparing FSH
• DDirect stimulation of Leydig cell proliferation independent of LH
• EPrimary synthesis within Sertoli cells