Based on its structure, which word most likely meanssomeone who takes advantage of circumstances?

The word that most likely means someone who takes advantage of circumstances is "opportunist." An opportunist is defined as a person who exploits circumstances or situations for their own benefit, often without regard for principles or ethics. This term is commonly used to describe individuals who prioritize personal gain over altruism, demonstrating a tendency to seize opportunities whenever they arise, regardless of the consequences for others.

In essence, an opportunist adapts to changing conditions to capitalize on them, often being flexible or even manipulative in their approach to achieve their objectives. The nuances of this term can carry both negative and positive connotations, depending on the context in which it is used.