Task: Question Answering
Input (English): Question: It is characteristic of the alpha helix: 
 Options:  <1> Present 3.6 amino acid residues per turn. <2> Be levorotatory <3> Be stabilized by intrachain disulfide bridges. <4> Present ionic bonds between amino and ketone groups loaded with peptide bonds. <5> Have the side chains of the amino acids inwards.
Output (English): 1