![](https://cos-cdn.shuashuati.com/pipixue-web/2020-1231-2005-12/ti_inject-812ce.png)
In the a helix, the hydrogen bonds:
A.
are roughly parallel to the axis of the helix.
B.
are roughly perpendicular to the axis of the helix.
C.
occur mainly between electronegative atoms of the R groups.
D.
occur only between some of the amino acids of the helix.
E.
occur only near the amino and carboxyl termini of the helix.