Which statement describes neutering?

• A. Neuter involves removal of ovaries
• B. Neuter involves tying off testicular tubes
• C. Neuter increases urine marking
• D. Neuter has no effect on aggression

Answer: (B)

Neutering is surgical sterilization that generally involves altering the reproductive organs and their connections so the animal can’t reproduce. In males, the common procedure is castration, where the testes are removed and the spermatic cord—which contains the blood vessels and the vas deferens (the ducts carrying sperm)—is ligated or tied off. This ligation of the ducts and vessels effectively sterilizes the animal. That description fits the statement about tying off testicular tubes, making it the best choice.

Removing ovaries describes a female procedure (spaying) and isn’t a complete description of neutering as a concept. Neutering does not universally increase urine marking; in fact, it can reduce certain behaviors in some dogs, but results vary. And while neutering can influence aggression due to hormonal changes, it does not have a universal, guaranteed effect on aggression, so that statement isn’t an accurate general description either.