Correct option is A
- "On" is a preposition indicating the location of the man in relation to the cot.
- "Man" is a noun referring to a person.
- "Is" is a verb helping to form the present continuous tense of "sleeping."
- "The" is a definite article used to specify the noun "man."
- Since "on" is showing the relationship between "sleeping" and "cot," it is the preposition in the sentence.
