Digestive system is best defined as a group of organs that primarily function to:
Answer: B) Break down food into usable molecules. For Digestive System, once you lock onto the key mechanism or definition, Break down food into usable molecules is the clear fit. If you restate the concept in your own words, the functional job described in the stem is exactly what Break down food into usable molecules does in Digestive System. So Break down food into usable molecules is the clean, accurate selection. If a similar stem appears later, start from the same core fact and you will land on the same kind of answer. In class notes, highlight this same phrase next to the related diagram so the wording and the picture reinforce each other.
Ref: Animal physiology is Unit 7 of the CSIR NET Life Science Syllabus, covering core body systems. It accounts for roughly 10% of the total marks in Sections B and C.