Answer: Option A .
In a coil by Hydrogen bonding.
Explanation:
B - pleated sheet secondary structure of protein is a regular element of secondary protein structure which consist of beta strands. In B pleated sheet, two or more segments or strands of polypeptide chain lie at the side of each other to form sheet which is held by Hydrogen bonding. The G in B pleated sheet form a coil and are held by Hydrogen bonding. This bond is formed by carbonyl and amino acid group.