Final answer:
Social groups are an example of a stakeholder group that most strongly affects public perceptions and opinions about a company's socially responsible behavior.
Step-by-step explanation:
Under the stakeholder model, social groups would be an example of a stakeholder group that most strongly affects public perceptions and opinions about the company's socially responsible behavior. Social groups, such as environmental activists, have a strong impact on how people think about issues and can influence public opinion over time.