RAS question
Which Venn diagram best represents the relationship among: Elephants, Herbivores, Mammals?
Correct answer: (B) Elephants inside both Herbivores and Mammals, Herbivores and Mammals overlapping.
Elephants should be placed in the overlapping region of Herbivores and Mammals, because every elephant is both a herbivore and a mammal.
Explanation
The right Venn diagram is the one where Herbivores and Mammals overlap, and Elephants lie inside that common part. All elephants are herbivores and all elephants are mammals, while the larger sets do not contain each other fully. NCERT's Class VII Science Exemplar supports the herbivore side by listing Elephant under Herbivores. The overlap is necessary because some herbivores are not mammals, such as the tortoise example, and some mammals are not herbivores, such as the lion example. Therefore, Elephants are not a larger enclosing class; they are a subset sitting where the two broader classes intersect.
Why the other options are wrong
- (A) It wrongly makes all herbivores mammals, although tortoise is a herbivore that is not a mammal.
- (C) Three separate circles would deny any common membership, but elephants are both herbivores and mammals.
- (D) It wrongly puts all mammals inside herbivores and separates elephants, even though elephants belong to both categories.
Concept
This tests Venn diagrams for class inclusion and partial overlap. It recurs in RAS reasoning because animal or object groups often look nested at first, but the exam expects precise set logic.