Which of the following is an example of a public good?

A lighthouse is an example of a public good among the options provided. Public goods are characterized by being non-excludable and non-rivalrous, meaning that individuals cannot be prevented from using them, and one person's use does not reduce availability for others. A lighthouse fits this description because its light serves all ships in the vicinity without excluding any and its use by one ship does not diminish its utility for others. In contrast, laptops, movie tickets, and restaurant meals are private goods, as they are both excludable (only those who pay can use them) and rivalrous (one person's consumption reduces availability for others).