Definition of legal drugs: which describes drugs approved for sale either over the counter or by prescription?

• A. Illegal
• B. Over the Counter
• C. Prescription Drugs
• D. Drugs Approved for Sale Either Over the Counter or by Prescription

Answer: (D)

Legal drugs are those that have been approved by a regulatory authority for sale, either over the counter or by prescription. This means they’ve gone through safety and efficacy evaluations and are sold with proper labeling. The description that covers both categories—drugs approved for sale either over the counter or by prescription—is the best one because it includes all legally sold medicines. The other options describe only part of the picture (illegal, over the counter alone, or prescription drugs alone) and thus don’t fully capture what legally sold drugs are. For example, aspirin is an over-the-counter legal drug, while many antibiotics require a prescription.