Answer: Option (c) is the correct answer.
Step-by-step explanation:
A mixture which consists of solute particles that are unevenly distributed into the solvent is known as a heterogeneous mixture.
For example, a mixture of gases in the air used to inflate a flattened bicycle tire will be a homogeneous mixture because the gases present in the air are evenly distributed.
A homogeneous mixture is a clear solution in which you cannot see the particles.
On the other hand, a homogeneous mixture is defined as the mixture in which solute particles are evenly distributed in a solvent.
For example, concrete is a heterogeneous mixture because in it sand and mortar will be unevenly distributed.
In a heterogeneous mixture particles can be easily seen with naked eye.
Thus, we can conclude that out of the given options concrete in which you can see the sand and mortar that make up the mixture is a heterogeneous mixture.