Final answer:
High temperature, particularly moist-heat sterilization in an autoclave, is the most effective method for destroying bacterial endospores, compared to pressure, chemical disinfectants, or radiation.
Step-by-step explanation:
The most important measure to ensure the destruction of bacterial endospores is high temperature. Endospores are highly resistant to extreme conditions, including pressure and chemical disinfectants. However, moist-heat sterilization, such as that achieved in an autoclave, is able to penetrate and denature the proteins within endospores, leading to their destruction, making it the method of choice for sterilization in medical and laboratory settings.