Final answer:
The correct example of deductive reasoning among the given options is C, where it logically applies a general statement about planets to the specific case of Mars.
Step-by-step explanation:
The example of deductive reasoning in the given options is C: 'Planets are round. Mars is a planet. Therefore, Mars is round.' Deductive reasoning involves starting with a general statement and applying it to a specific case. It often follows a pattern where the argument moves from a general premise to a specific conclusion. In this example, the general statement is that all planets are round, which is applied to the specific case of Mars. Hence, since Mars is a planet, it must also be round according to the premise.
Option D: 'Rats are rodents. Mice are rodents. Therefore, mice are rats,' represents a logical fallacy known as a syllogism error or undistributed middle. It incorrectly assumes that two members of a broad category must belong to the same specific subset solely based on their shared membership in the broad category. Therefore, it does not correctly follow the proper structure for deductive reasoning.