Answer: Symbiotic association between fungi and plant roots.
- A A root-rot disease caused by parasitic fungal infection
- B Symbiotic association between fungi and plant roots
- C A form of asexual spore-based reproduction occurring within fungal hyphae
- D A free-living photosynthetic alga found in freshwater and marine habitats
Correct answer: B. Symbiotic association between fungi and plant roots
Explanation: Mycorrhiza is the mutualistic symbiosis between fungi (myco-) and plant roots (-rhiza). The fungus increases nutrient (especially phosphorus) and water absorption; the plant provides carbohydrates to the fungus.
Plants evolved from water-dependent algae through increasingly land-adapted groups, gaining vascular tissue (Pteridophyta), then seeds (Gymnosperms), and finally fruit-enclosed seeds (Angiosperms) - each step reducing dependence on water for reproduction.
Concept context
Classification of plants from algae to angiosperms. Understanding plant diversity is essential for NEET.