Correct answer: (a) 1, 3 and 4 only
Explanation
- A
1, 3 and 4 only
1, 3 and 4 only. Alfalfa, chickpea and clover are legumes (nitrogen-fixing). Amaranth, purslane and spinach are not.
- B
1, 3, 5 and 6 only
1, 3, 5 and 6 only. Kulfa and spinach do not fix N2.
- C
2, 4, 5 and 6 only
2, 4, 5 and 6 only. Drops the true legumes.
- D
1, 2, 4, 5 and 6
1, 2, 4, 5 and 6. Amaranth is not a fixer.
Summary. Official key is (a) 1, 3 and 4 only. Alfalfa, chickpea and clover are Fabaceae with Rhizobium. Amaranth, purslane (kulfa) and spinach are leafy non-legumes.
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