Public Goods: Non-Excludable and Non-Rivalrous

Steps:

• Define a public good as something non-excludable (no one can be prevented from using it) and non-rivalrous (one person's use doesn't reduce availability for others).
• Evaluate each option against this definition.
• Identify which option fits both criteria perfectly.
• Confirm by recalling standard economic examples.

Why B is correct:

• Street lights are non-excludable (everyone benefits without payment) and non-rivalrous (one person's illumination doesn't dim it for others), per the classic economic definition of public goods.

Why the others are wrong:

• A. Healthcare is excludable (access requires payment or eligibility), making it a private good.
• C. Unemployment benefits are excludable (only eligible recipients receive them) and rivalrous (limited government funds).
• D. Vaccinations are often excludable (require individual access or payment) and rivalrous in supply.

Final answer: B