Correct Answer: GREEN

Solution : Given:
INTELLIGENCE

Now, let's compare all the option words with the word INTELLIGENCE –
First option: GENTLE; All the letters of GENTLE are present in the word INTELLIGENCE.
Second option: TEEN; All the letters of TEEN are present in the word INTELLIGENCE.
Third option: GREEN; All the letters of GREEN are not present in the word INTELLIGENCE. R is not present in the word INTELLIGENCE.
Fourth option: ENGINE; All the letters of ENGINE are present in the word INTELLIGENCE.

So, from the above, only GREEN cannot be formed using the letters of the word INTELLIGENCE. Hence, the third option is correct.