Select the most appropriate option that can substitute the underlined words in…

One-word-substitution / synonym-selection questions test whether a single word can replace a descriptive phrase while keeping the exact same sense and tone as the original wording.

The underlined phrase describes Arjun as someone who "went out of his way to help others without expecting anything in return" — freely giving his time and effort to others with no expectation of reward. This is precisely the meaning of "generous": willing to give or share freely.

Checking the remaining options against the same phrase confirms none of them fit:

• "Greedy" means having an excessive desire to acquire more for oneself — the opposite of freely helping others.

• "Selfish" means being concerned only with one's own interests — again the opposite of going out of one's way for others.

• "Stingy" means being unwilling to give or spend — this contradicts the idea of helping without expecting anything back.

So the word that correctly substitutes the underlined phrase is "generous."