Write the therapeutic action of following on human body and mention the class of drugs to which each of these belong :
(i) Ranitidine (ii) Morphine (iii) Aspirin

Explanation

### Step-by-Step Solution:

1. **Ranitidine**
- **Therapeutic Action**: Ranitidine is primarily used to reduce stomach acid production. It works by blocking the action of histamine on the histamine H2 receptors in the stomach lining. This leads to a decrease in the secretion of gastric acid (HCl), which helps in treating conditions like hyperacidity and gastroesophageal reflux disease (GERD).
- **Class of Drug**: Ranitidine belongs to the class of drugs known as **H2 receptor antagonists** (or **antacids**).

2. **Morphine**
- **Therapeutic Action**: Morphine is an opioid analgesic used for the relief of moderate to severe pain. It acts on the central nervous system (CNS) to alter the perception of pain and emotional response to pain. Morphine is also used in post-operative settings and for cardiac pain relief. Additionally, it can induce sedation and euphoria.
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