Explanation

Step 1: Identify the letter G in the alphabet. G is the 7th letter. 

Step 2: Find the letter that is four to the left of G. Counting four letters back from G: F (6), E (5), D (4), C (3).

So, four letters to the left of G is C.

Step 3: Now, find the letter immediately to the left of C, which is B.

Step 4: Finally, determine the letter that is three to the right of B.

Counting three letters forward from B: C (1), D (2), E (3). 

Thus, the letter three to the right of B is E..