Final answer:
The mons pubis protects the pubic symphysis. It is a fatty pad located over the pubic bone and becomes covered in pubic hair after puberty.
Step-by-step explanation:
The structure that protects the pubic symphysis is the mons pubis. The mons pubis is a pad of fat located at the anterior, over the pubic bone, and after puberty, it is covered in pubic hair. The other options listed, such as the perineum, urethra, and labia, have different functions and do not specifically protect the pubic symphysis. The perineum is the region between the pubic symphysis and the coccyx. The urethra is a tube that connects the urinary bladder to the genitals for the removal of fluids from the body. The labia, comprising of the labia majora and labia minora, serve to protect the external genitalia and the entrance to the reproductive tract.