To decode the word "JAPAN" to "KCSES" and find the corresponding code for "CASTLE", we need to analyze the pattern used in the given code conversion.
Let's first examine how "JAPAN" is encoded as "KCSES":
We observe that each letter in "JAPAN" is shifted by an incremental number of positions forward in the alphabet (1 to 5). Thus, we apply the same pattern to the word "CASTLE".
Let's encode "CASTLE" using the same shifts:
This gives us the code "DCVXQK" for "CASTLE".
Thus, the correct answer is DCVXQK.
This coding pattern involves incrementing the shift value by one for each successive letter in the word.