Which of the following is a characteristic of living organisms that is directly enhanced by regular physical training?

Eliminate incorrect options: Lack of cellular organization is not a characteristic of living organisms, as all living organisms are highly organized at the cellular level. Production of inorganic molecules is not a defining feature of living organisms, as they primarily produce organic molecules. The ability to photosynthesize is specific to plants, algae, and some bacteria, not all living organisms.

Connect physical training to homeostasis: Physical training improves the body's efficiency in maintaining homeostasis. For instance, it enhances thermoregulation (e.g., sweating to cool down) and metabolic processes, which are critical for maintaining a stable internal environment.