A mixture in which two or more substances are blended evenly throughout.

• A. Heterogeneous mixture
• B. Homogeneous mixture
• C. Colloid
• D. Solution

Answer: (B)

Uniform composition in a mixture means the substances are distributed evenly throughout, so every portion has the same proportions. That is exactly what a homogeneous mixture is: a mixture whose components are blended evenly across the entire sample, so you can't see or separate the substances just by looking. A heterogeneous mixture would have visible different parts, not evenly mixed. A colloid looks uniform but the particles are larger than molecules and may not be evenly distributed at all scales. A solution is a specific type of homogeneous mixture where the substance is dissolved at the molecular level, but the general term homogeneous mixture captures the idea of even distribution across the whole mixture. Thus, the described situation corresponds to a homogeneous mixture.