A particular solution contains molecules and ions of the solute. Therefore, it is a:
(a) weak acid
(b) strong acid
(c) strong base
(d) salt solution

Options

A. weak acid
B. strong acid
C. strong base
D. salt solution

Answer

To determine the nature of the solution that contains both molecules and ions of the solute, we can analyze the options provided:

1. **Understanding the Definitions**:
- **Weak Acid**: A weak acid only partially dissociates in solution, meaning that both the undissociated molecules and the ions (H⁺ and A⁻) will be present.
- **Strong Acid**: A strong acid completely dissociates in solution, resulting in only ions (H⁺ and A⁻) being present, with no undissociated molecules.
- **Strong Base**: A strong base also completely dissociates in solution, resulting in only ions (B⁺ and OH⁻) being present.
- **Salt Solution**: A salt solution is formed from the reaction of an acid and a base, and it typically contains only ions, with no undissociated molecules.

2. **Analyzing the Given Information**:
- The question states that the solution contains both molecules and ions of the solute. This indicates that there must be some undissociated molecules present along with the ions.

3. **Evaluating the Options**:
- **Option (a) Weak Acid**: This is a valid option because a weak acid will have both undissociated molecules and ions present.
- **Option (b) Strong Acid**: This option is not valid because a strong acid would not have any undissociated molecules, only ions.
- **Option (c) Strong Base**: This option is also not valid for the same reason as the strong acid; a strong base would not have undissociated molecules.
- **Option (d) Salt Solution**: This option is not valid because a salt solution consists only of ions, with no undissociated molecules.

4. **Conclusion**:
- Since the only option that allows for the presence of both molecules and ions is the weak acid, the correct answer is **(a) weak acid**.

### Final Answer:
The solution is a **weak acid**.