Final answer:
The form of the Undistributed Middle is a logical fallacy in deductive reasoning where the middle term is not distributed in the premises, resulting in an invalid conclusion.
Step-by-step explanation:
The form of the Undistributed Middle is a logical fallacy. It is a type of invalid deductive reasoning where the middle term in a syllogism is not distributed (or referenced to all) in the premises, leading to an invalid conclusion. This fallacy occurs when there is a common term in both premises but it does not establish a logical connection between the subjects in the premises, making the conclusion invalid.