Choose the most suitable option to replace the highlighted part of the sentence:
The doctor advised him to avoid eating sweets and doing exercise regularly.

Correct option is C

The correct substitution of the highlighted words is (c) to avoid eating sweets and to exercise regularly.
Explanation: The verb advise when followed by an object often takes a to-infinitive (advised him to…). We need parallel structure for the two coordinated actions: to avoid … and to exercise …. Option (c) maintains both the correct complementation after advised him and parallelism.
Grammatical rule used:
i) Verb + object + to-infinitive after advise, tell, ask etc.
ii) Parallelism: items joined by and must have the same grammatical form (to-infinitive + to-infinitive).
Example: The coach advised the players to hydrate well and to rest adequately.
Information booster / exceptions: After advise + gerund is also possible without an object (The doctor advised avoiding sweets), but once an object (him) is present, to-infinitive is preferred: advised him to avoid….
Meanings of the given other options:
· (a) avoiding sweets and doing regular exercise: breaks structure after advised him; lacks required to-infinitive. (Hindi: rūp asangati)
· (b) to avoid sweets and to exercises regularly: subject–verb form error exercises (should be exercise). (Hindi: galat rūp)
· (d) to not eat sweets and do exercises: split infinitive “to not eat” is acceptable in modern usage but here do exercises is awkward/unparallel; also shifts collocation. (Hindi: aprākrit sanyojan)