Which of the following statements about `H_(3)BO_(3)` is not correct ?

Options

A. It is a strong tribasic acid.
B. It is prepared by acidifying an aqueous solution of borax.
C. It has a layer structure in which planar `BO_(3)`, units are joined by hydrogen bonds.
D. It does not act as proton donor but acts as a Lewis acid by accepting a lone pair of electrons.

Explanation

To determine which statement about H₃BO₃ (boric acid) is not correct, let's analyze each statement one by one.

1. **It is a strong tribasic acid.**
- This statement is **not correct**. H₃BO₃ is actually a very weak acid and behaves as a monobasic acid rather than a tribasic acid. It does not dissociate completely in solution.

2. **It is prepared by acidifying an aqueous solution of borax.**
- This statement is **correct**. Boric acid can be prepared by the acidification of borax (Na₂B₄O₇) with an acid, typically hydrochloric acid.

3. **It has a layered structure in which planar BO₃ units are joined by hydrogen bonds.**
- This statement is **correct**. Boric acid has a layered structure where the planar BO₃ units are indeed linked by hydrogen bonds.

4. **It does not act as a proton donor but acts as a Lewis acid by accepting a lone pair of electrons.**
- This statement is **correct**. Boric acid does not donate protons in the traditional sense but can accept a lone pair of electrons, thus acting as a Lewis acid.

Based on this analysis, the statement that "It is a strong tribasic acid" is the one that is not correct.

### Summary of the Solution:
- The incorrect statement about H₃BO₃ is that it is a strong tribasic acid. In reality, it is a very weak monobasic acid.