Answer: Option (b) is the correct answer.
Explanation:
A solution whose constituent particles are uniformly distributed in the solution is known as a homogeneous solution.
In a homogeneous solution, particles of one solute completely dissolves in the solvent. This solution is also known a true solution.
When sand and water are mixed together then after a certain interval of time sand particles will settle at the bottom. Therefore, they do not dissolve in water. So, it is not a homogeneous solution.
When salt and water are mixed together then the salt particles will dissolve in water. Therefore, it is a homogeneous solution.
Salad dressing is not a homogeneous solution as it contains different solutions like oil, lemon juice etc which does not dissolve when mixed together.
On the other hand, soil is also not a homogeneous solution because we can visualize the distinct layers present in a soil. These layers when mixed in a solution does not dissolve so they did not form a homogeneous solution.
Thus, we can conclude that out of the given options, salt and water is a homogeneous mixture.
