Select the most appropriate option that can substitute the highlighted segment in the given sentence.
Shubhda has not finished to paint the window.

Correct option is C

The correct substitution of the highlighted words is (c) painting.
Explanation: After the verb finish, we use a gerund (-ing form), not an infinitive. Therefore, “has not finished painting the window” is correct.
Options (a), (b), and (d) either add unnecessary prepositions or change the meaning: painting on suggests the surface/location, painting of makes a noun phrase (a painting of the window), and painting with indicates the instrument/material.
Grammatical rule used:
Certain verbs (e.g., admit, avoid, consider, deny, enjoy, finish, keep, mind, suggest) are followed by gerunds. Structure: verb + -ing (finish doing, stop talking, enjoy reading).
Example: She finished writing the report before lunch. (Not: finished to write)
Information booster / exceptions: Some verbs can take either to-infinitive or -ing with meaning changes (e.g., remember/forget/try/stop: stop to smoke vs stop smoking). But finish strictly takes -ing.