Final answer:
Science is a branch of knowledge that studies the natural world to gain knowledge and understanding. In the context of biology, it studies living organisms and their interactions with each other and the environment.
Step-by-step explanation:
The statement that best describes science is option A: Branch of knowledge that studies the natural world to gain knowledge and understanding. Science is a distinctive way of gaining knowledge about the natural world based on evidence and logic. It attempts to describe and understand the nature of the universe. In the context of biology, science studies living organisms and their interactions with one another and their environments.