**Core Concept**
Beta blockers are a class of medications that inhibit the effects of the sympathetic nervous system on the heart and blood vessels. Beta 2 receptor agonist action, on the other hand, stimulates beta 2 adrenergic receptors, causing smooth muscle relaxation, particularly in the bronchi and blood vessels. A medication that combines both properties can be used to treat conditions such as hypertension and bronchospasm.

**Why the Correct Answer is Right**
The correct answer is **C. Xamoterol**. Xamoterol is a beta blocker that also has beta 2 receptor agonist activity. This unique combination allows it to provide vasodilation and reduce blood pressure, while also causing bronchodilation. The beta 2 agonist action is thought to be responsible for the medication's bronchodilatory effects, which can be beneficial in patients with asthma or chronic obstructive pulmonary disease (COPD).

**Why Each Wrong Option is Incorrect**
**Option A:** **Pindolol** is a beta blocker, but it does not have significant beta 2 receptor agonist activity.
**Option B:** **Acebutolol** is a beta blocker with partial beta 1 selectivity, but it does not have beta 2 agonist properties.
**Option D:** **Sotalol** is a beta blocker, but it is primarily used for its antiarrhythmic properties and does not have beta 2 agonist activity.

**Clinical Pearl / High-Yield Fact**
Xamoterol's unique combination of beta blocking and beta 2 agonist actions makes it a useful medication for patients with hypertension and respiratory disease. However, its use is limited due to concerns about its potential for causing bronchospasm in some patients.

**Correct Answer:** C. Xamoterol