`H_3PO_3` is a................ Basic acid.

Explanation

To determine the basicity of the acid \( H_3PO_3 \), we need to analyze its structure and the number of hydroxyl groups (\( OH \)) it contains. Here’s a step-by-step solution:

### Step 1: Identify the central atom
The central atom in \( H_3PO_3 \) is phosphorus (P).

**Hint**: Look for the atom that is bonded to multiple other atoms in the molecule.

### Step 2: Analyze the structure of \( H_3PO_3 \)
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