Which of the following is NOT a reason for filing a civil lawsuit?

Filing a civil lawsuit typically involves disputes between private parties regarding rights, obligations, and remedies that can be pursued in a court setting. Each of the first, third, and fourth options represents a valid reason for initiating a civil lawsuit.

To enforce a contract is a fundamental basis for civil litigation, as individuals or organizations can seek to ensure that terms agreed upon in a contract are honored. Similarly, collecting damages for injury is another common motive, allowing plaintiffs to seek compensation for harm suffered due to another party's actions. Protecting civil rights also falls within the civil litigation framework, where individuals can challenge violations of their rights and seek remedies.

However, recovering custody of a child typically falls under the jurisdiction of family law and is often addressed through family court proceedings rather than through civil lawsuits in a general context. While custody disputes can involve legal proceedings, they are not classified as civil lawsuits in the same way as contract enforcement, personal injury claims, or civil rights protections are. Thus, this option does not align with the typical premises for filing a civil lawsuit.