Which term best describes a detrimental effect caused by external factors?

The term that best describes a detrimental effect caused by external factors is "havoc." This word specifically refers to widespread destruction or devastation, often resulting from negative influences or events. In contexts such as law enforcement or highway safety, "havoc" conveys the seriousness and substantial impact of adverse circumstances that can disrupt order and safety, emphasizing the gravity of the situation.

Considering the other terms, "benefit" refers to a positive outcome or advantage, which clearly does not align with the idea of a detrimental effect. "Impact" is a more neutral term that could refer to either positive or negative influences, but it does not carry the strong connotation of destruction that "havoc" does. Lastly, "support" denotes assistance or reinforcement, which is the opposite of causing a detrimental effect. Therefore, "havoc" is the most appropriate choice for describing severe negative consequences resulting from external factors.