Correct Answer - Option 3 : 81
EXPLANATION:
REPTILE is a 7 letter word and square of 7 is 49.
∴ The code for REPTILE is 49 . Same we can apply to SNAKE. SNAKE is a 5 letter word and it is coded as 25. 25 is the square of 5.
∴ according to this logic CROCODILE is a 9 letter word and square of 9 is 81.
Hence option 3 is the right answer.