Explanation:

- Three years ago, the average age of A, B, and C was 29 years. This means their total age was:

$$3\times 29=87\text{ years}$$

So, $$A+B+C=87+3\times 3=96\text{ years (present age)}$$

- Five years ago, the average age of B and C was 23 years. This means their total age was:

$$2\times 23=46\text{ years}$$

So, $$B+C=46+2\times 5=56\text{ years (present age)}$$

- Given $$A+B+C=96$$ and $$B+C=56$$, we find:

$$A=96-56=40$$

- Thus, the present age of A is: 40

- Option 2 is correct: 40