Explanation: All except the urethra in the give options do not exist as a pair in the body system. The urethra is defined anatomically as the tube through which urine exits the body and, in penises, is the tube through which semen is ejaculated. It is the tube that connects the urinary bladder to the urethral opening on the external genitals in both males and females.
Renaissance was a period of European history that was very disputed.
This period was a hierarchal age and the place of a person in the society was determined by the class that he/she was born into it.
However, the hierarchy was not limited to just rank but also included gender which was defended by revolutionary women as gender was considered as a natural distinction.
Thus, revolutionists in the process of equalisation wanted to defend gender the most.