$\begin{array}{1 1}\text{(a) secondary structures are $\rho$ helix and $\beta$}\\\text{(b) secondary structures are $\alpha$ helix and $\gamma$}\\\text{(c) secondary structures are $\alpha$ helix and $\beta$}\\ \text{(d) secondary structures are $\delta$ helix and $\beta$}\end{array} $
