D) They both look uniform (the same) throughout.
<h3>Further explanation</h3>
Pure substance can be any element or compound and is formed from one type of atom/molecule only
Meanwhile, the solution is included in a mixture consisting of 2 or more pure substance
Pure substance can be formed through a chemical process while the mixture is through a physical process
Mixture can be separated by physical processes into components of pure substance while pure substance cannot
The mixture itself consists of a homogeneous and heterogeneous solution
The mixture can be divided into a homogeneous mixture if the composition/ratio of each substance in the mixture is the same and a heterogeneous mixture if the ratio of the composition of the substances is not the same (can be varied) in each place.
Mixtures can also be divided into solutions, suspensions, and colloids based mainly on the size of the particles
Homogeneous mixture = Solution
Heterogeneous mixture = suspension, and
The mixture is located between suspension and solution = Colloid
