Which of the following is an example of an antipyretic drug?

Ibuprofen is an example of an antipyretic drug because it has the ability to reduce fever. It achieves this by inhibiting enzymes involved in the production of prostaglandins, which are responsible for producing fever as part of the body’s inflammatory response. This makes ibuprofen effective not only as a pain reliever but also as a medication that helps to lower elevated body temperature.

The other options listed serve different purposes. Morphine is primarily an opioid analgesic used for pain management and does not possess antipyretic properties. Meperidine, like morphine, is an opioid that is primarily used for pain relief and does not have a role in reducing fever. Codeine, another opioid, is also used for pain relief and cough suppression, rather than for reducing fever. Thus, among the choices provided, ibuprofen stands out as the appropriate choice for an antipyretic drug.