Which of the following is not an alien species in India?

The correct answer is Option (2) → Elephant Grass

Option (1) Water hyacinth — Alien. Water hyacinth.

Option (2) Elephant Grass — Not alien. Elephant grass is not named among the alien species.

Option (3) Carrot Grass — Alien. Carrot grass (Parthenium).

Option (4) Lantana — Alien. Lantana.

NCERT Extract:
Loss of Biodiversity – “… (iii) Alien species invasions: When alien species are introduced unintentionally or deliberately for whatever purpose, some of them turn invasive, and cause decline or extinction of indigenous species. The Nile perch introduced into Lake Victoria in east Africa led eventually to the extinction of an ecologically unique assemblage of more than 200 species of cichlid fish in the lake. You must be familiar with the environmental damage caused and threat posed to our native species by invasive weed species like carrot grass (Parthenium), Lantana and water hyacinth (Eicchornia). The recent illegal introduction of the African catfish Clarias gariepinus for aquaculture purposes is posing a threat to the indigenous catfishes in our rivers.”
Loss of Biodiversity – “… You must be familiar with the environmental damage caused and threat posed to our native species by invasive weed species like carrot grass (Parthenium), Lantana and water hyacinth (Eicchornia).”