Correct Answer: TRUCK

Solution : Given:
CONSTRUCTION

Now, let's compare all the option words with the word CONSTRUCTION –
First option: CRUST; All the letters of CRUST are present in the word CONSTRUCTION.
Second option: STUNT; All the letters of STUNT are present in the word CONSTRUCTION.
Third option: TRUCK; K is not present in the word CONSTRUCTION. Therefore, all the letters of TRUCK are not present in the word CONSTRUCTION.
Fourth option: COTTON; All the letters of COTTON are present in the word CONSTRUCTION.

So, from the above, only TRUCK cannot be formed from the word CONSTRUCTION. Hence, the third option is correct.