I am hallucinating , he thought . Slowly , with great caution , the creature broke the surface . He was , Atobe realised almost at once , rather short - sighted , which explained the squinting .

Based on the preceding passage, choose your answer for question Why does the narrator feel they are under the spell of hallucinogens ?
OPTIONS:
[I] The narrator is seeing a strange monster .
[II] None of the above choices .
[III] The narrator is under the influence .
[IV] The narrator has taken drugs .
The answer is:
[I]