Final answer:
The taste of mixture b compared to mixture c cannot be determined without specific information on their components. Mixture b as an element is unlikely to have a taste, while mixture c's taste could vary depending on its makeup and individual taste receptors or genetic factors.
Step-by-step explanation:
The comparison between the taste of mixture b and mixture c is not directly provided. However, if mixture b is an element, it likely does not have a taste as elements in their pure form are generally not consumable or do not have distinctive flavors.
On the other hand, the reference to gustation and different mixtures suggests that mixture c could be a solution or another type of homogeneous mixture with varying ratios of components which would affect its taste. Having different proportions of ingredients will result in varying tastes, as described by the sugar-water example where more sugar results in a sweeter taste.
Additionally as the perception of taste can depend on the type of taste receptor and genetics, the tasting experience can vary between individuals. If mixture c involves a compound like PTC mentioned in the context genetic factors could play a role in the taste perceived. Thus comparing mixtures b and c is challenging without specific information about the components of each mixture.