(A) Adjective
(B) Preposition
(C) Averb
(D) None of these
🧠 Explanation:
- The word “till” shows the relationship between the action of working and the time it ended.
- It links two time points: the start (9am) and the end (8pm) of the action.
- Such words that establish a link between nouns or pronouns and other elements are used to express time, place, or direction.
- Therefore, in this context, it functions as a connecting word that relates to time.