Which Backbone Arrangement BEST Represents That of Two Peptide Bonds $\alpha$

Multiple Choice

Which backbone arrangement BEST represents that of two peptide bonds?

A) C _$\alpha$ -N-C _$\alpha$ -C-C _$\alpha$ -N-C _$\alpha$ -C
B) C _$\alpha$ -N-C-C-N-C _$\alpha$
C) C-N-C _$\alpha$ -C _$\alpha$ -C-N
D) C _$\alpha$ -C-N-C _$\alpha$ -C-N
E) C _$\alpha$ -C _$\alpha$ -C-N-C _$\alpha$ -C _$\alpha$ -C