Okay, let's tackle this question. The user provided a question about beta blockers and the correct answer is missing. First, I need to recall which beta blockers are selective and which are non-selective.

Selective beta blockers target beta-1 receptors, mainly in the heart, while non-selective block both beta-1 and beta-2, which are in the lungs and other areas. Common selective ones are metoprolol, atenolol, bisoprolol. Non-selective include propranolol, nadolol, timolol.

The question asks which one is NOT selective, so the correct answer should be a non-selective blocker. If the options include propranolol, timolol, or nadolol, those would be the right answers. But the user didn't list the options, so I need to make sure my explanation covers common examples.

In the explanation, I'll start with the core concept of beta blocker selectivity. Then explain why non-selective ones are the exception here. The incorrect options would be the selective ones. The clinical pearl should highlight that non-selective beta blockers can cause bronchoconstriction, so contraindicated in asthma. Need to keep the answer concise but thorough, within the character limit.

**Core Concept**: Selective beta blockers (beta-1 selective) preferentially block cardiac beta-1 adrenergic receptors, minimizing bronchial/smooth muscle effects. Non-selective beta blockers block both beta-1 and beta-2 receptors, increasing risk of bronchoconstriction.

**Why the Correct Answer is Right**: Propranolol is a **non-selective beta blocker**, inhibiting both beta-1 and beta-2 receptors. This lack of selectivity increases the risk of bronchoconstriction, making it contraindicated in asthma. Other non-selective agents include timolol and nadolol.

**Why Each Wrong Option is Incorrect**:
**Option A: Metoprolol** – Selective beta-1 blocker; used in hypertension and angina.
**Option B: Atenolol** – Selective beta-1 blocker; commonly prescribed for hypertension.
**Option C: Bisoprolol** – Selective beta-1 blocker; indicated for heart failure and angina.

**Clinical Pearl**: *Remember "PROPRIETARY" – Propranolol, Pindolol, Timolol (non-selective). Selective agents end with "-lol" but exclude those in the proprietary list. Avoid non-selective beta blockers in patients with respiratory conditions.

**Correct Answer**: **A. Propranolol**

✓ Correct Answer: D. Celiprolol