A solution is a mixture of a:

• A. compound and an element
• B. acid and a base
• C. solid and a gas
• D. solute and a solvent

Answer: (D)

Verified step by step guidance

1. Understand the definition of a solution in chemistry: a solution is a homogeneous mixture where one substance (the solute) is dissolved in another substance (the solvent).
2. Recognize that the solute is the component present in a smaller amount, and the solvent is the component present in a larger amount.
3. Note that solutions can involve different phases, such as solid, liquid, or gas, but the key characteristic is the uniform distribution of the solute within the solvent.
4. Evaluate the given options: 'compound and an element', 'acid and a base', 'solid and a gas'—none of these pairs specifically describe the components of a solution.
5. Conclude that the correct description of a solution is a mixture of a solute and a solvent, which aligns with the fundamental chemistry definition.