Correct Answer - Option 3 : X
9YZ
Here the numbers are written in square form like (2)2, (3)2, (4)2, (5)2 and so on.
In each word, the numbers are written below in every next position like in 3rd term number is written below in 2nd position, in 4th term number is written below 3rd position.
In first word it is XYZ4. So, the next number must be 9 and it should be written below the letter which is next to Z I.e. X.
Hence, X9YZ is the correct answer.