Correct option A: 0.017 cm
Length of fully extended (naked) 50 Mb chromosome stretch = 50
x106 bases x 0.34 nm
                                                              Â
          = 17.0
x 106
nm                   Â
              Â
[1nm = 10-9 m]
         = 1.7 x
10-2 m = 0.017 cm
              Â
[1 m = 100 cm]
Rise per base pair means the vertical distance (elevation)
between two adjacent bases as they rise along the helix. It gives
the length of the naked DNA itself.