15. Which of the following descriptions about nucleotide and nucleic acid structures is(are) correct?1. The double helix of DNA in the B-form is stabilized by covalent bonds between the 3' end of one strand and the 5' end of the other.2. The double helix of DNA in the B-form is stabilized by nonspecific base-stacking interaction between two adjacent bases in the same strand.3. In nucleotides and nucleic acids, syn and anti conformations relate to rotation around the phosphodiester bond.4. C-5 of the pentose in nucleic acids is joined to a nitrogenous base.5. The phosphodiester bond that joins adjacent nucleotides in DNA is susceptible to alkaline hydrolysis.(A) 1 and 2.(B) 2 and 3.(C) 3 and 4.(D) 2 only.(E) 2 and 5.