Solution

In this code, each letter is replaced with the letter that comes after it. However, this difference keeps increasing by one for every subsequent letter. This is how it works:   G - replace with next letter—H R - replace with the letter after the next letter – T E - replace with the letter two letters after the next letter – H E - replace with the letter three letters after the next letter— I K - replace with the letter four letters after the next letter – P   S - replace with next letter—T P - replace with the letter after the next letter – R A - replace with the letter two letters after the next letter – D I - replace with the letter three letters after the next letter— M N - replace with the letter four letters after the next letter – S   Thus, the code for SPAIN is TRDMS. Hence, the correct answer is (B).