A
Congress grass
B
Elephant grass
C
Lemongrass
D
Nut grass
Correct answer: (c) Lemongrass
Explanation
- A
Congress grass
Congress grass. Parthenium; an invasive weed, not the citronella-type repellent.
- B
Elephant grass
Elephant grass. Napier fodder.
- C
Lemongrass
Lemongrass. Citronella/citral oil; a natural mosquito repellent.
- D
Nut grass
Nut grass. Cyperus; a weed.
Summary. Official key is (c) lemongrass. Cymbopogon oils (citronella, citral) are the household natural mosquito repellent. The other three are grasses of other uses or weeds.
Same topic · past papers
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