What is the common name for acetylsalicylic acid, often used for pain relief?

Acetylsalicylic acid is most commonly known as Aspirin. It is widely used for its analgesic (pain-relieving), anti-inflammatory, and antipyretic (fever-reducing) properties. Aspirin works by inhibiting certain enzymes involved in the synthesis of prostaglandins, which are compounds that mediate inflammation, pain, and fever. Additionally, it has an antiplatelet effect, making it useful in preventing cardiovascular events.

The other options listed serve different purposes or are different compounds. Ibuprofen and naproxen are nonsteroidal anti-inflammatory drugs (NSAIDs) that also provide pain relief but are chemically distinct from acetylsalicylic acid. Acetaminophen, while effective for pain relief and fever reduction, does not have the anti-inflammatory properties characteristic of Aspirin. Therefore, the correct answer identifying acetylsalicylic acid is Aspirin.