Final answer:
The statement is (Option B) false; reptiles form a paraphyletic group if birds are not included, but the inclusion of mammals is irrelevant as they evolved from a separate amniotic lineage.
Step-by-step explanation:
The statement is regarding the phylogenetic classification of organisms and the concept of a paraphyletic group. In the classification of amniotes, which includes mammals, reptiles, and birds, reptiles are considered to form a paraphyletic group unless birds (avian reptiles) are included. This stems from birds having evolved from a group of theropod dinosaurs, which are traditionally considered reptiles. Therefore, including birds within Reptilia makes the group a true clade, whereas excluding birds makes it paraphyletic.
Given this context, the statement 'Reptile refers to a paraphyletic group unless we include birds and mammals in that group' is false because mammals are not part of the reptile clade. The correct inclusion would be of birds only, as they evolved from diapsid ancestors shared with reptiles.