How many of the following statements is/are not correct?
$(a)$ Presence or absence of hymen is a reliable indicator of virginity/sexual experience.
$(b)$ Vaginal orifice is completely closed by a septum of mucous membrane called hymen.
$(c)$ The uterus opens into urethra.
$(d)$ Vagina along with cervical canal forms birth canal.

• A
  $4$
• B
  $3$
• C
  $2$
• D
  $1$