Which of the following structures open into the prostatic sinus?
- The internal surface of the posterior wall of the prostatic urethra has a median ridge known as the urethral crest.
- A groove on each side, known as the prostatic sinus, receives the prostatic ductules.
- A rounded eminence located in the middle of the median ridge is known as the seminal colliculus.
- The prostatic utricle is an embryonic remnant of the uterus and part of the vagina.
- The ejaculatory ducts open beside the prostatic utricle.