**Core Concept**
NSAIDs (Non-Steroidal Anti-Inflammatory Drugs) are a class of medications that exert their effects through the inhibition of cyclooxygenase enzymes (COX), thereby reducing the production of prostaglandins and subsequent inflammation. However, not all NSAIDs have equal anti-inflammatory effects, as some may preferentially inhibit COX-2, which is primarily responsible for inflammation, while others may have minimal anti-inflammatory activity.

**Why the Correct Answer is Right**
Paracetamol (acetaminophen) is unique among the options as it has minimal anti-inflammatory activity. Unlike other NSAIDs, which inhibit both COX-1 and COX-2 enzymes, paracetamol primarily inhibits COX-3, an isoform that is present in the brain and spinal cord, thereby exerting its analgesic and antipyretic effects. The lack of significant COX-2 inhibition in paracetamol explains its reduced anti-inflammatory activity compared to other NSAIDs.

**Why Each Wrong Option is Incorrect**
**Option A:** Indomethacin is a potent COX-1 and COX-2 inhibitor, making it a strong anti-inflammatory agent.
**Option C:** Ketorolac is a non-selective COX inhibitor, which means it has significant anti-inflammatory activity.
**Option D:** Ibuprofen, while somewhat selective for COX-2, is still a potent anti-inflammatory agent.

**Clinical Pearl / High-Yield Fact**
When choosing an NSAID for anti-inflammatory purposes, selectivity for COX-2 over COX-1 is generally preferred to minimize gastrointestinal side effects. However, paracetamol's unique pharmacology makes it a good choice for analgesia and antipyresis without significant anti-inflammatory effects.

**✓ Correct Answer: B. Paracetamol**