If a Peptide Was Composed Entirely Of $\alpha$ -Helical Structure and Found to Contain an Integer Number of and Found

Multiple Choice

If a peptide was composed entirely of $\alpha$ -helical structure and found to contain an integer number of complete turns, which of the following would be a possible number of amino acid residues in the peptide?

A) 12
B) 20
C) 32
D) 36
E) 60