Which one of the following mixture is NOT homogeneous?

* Homogeneous mixtures have a uniform composition throughout their mass (e.g., Methanol + water, Alcohol + water, and Vinegar which is an aqueous solution of acetic acid).
Heterogeneous mixtures do not have a uniform composition. Soil contains a mixture of organic matter, sand, clay, minerals, and small pebbles unevenly distributed, making it a heterogeneous mixture.