Given figure represents the DNA double helix model as proposed by Waston and Crick (1953). Select the option that shown correct measurements of A, B and C.

Options

A. A-3.4nm,B-0.34 nm, C-2 nm
B. A-3.4nm, B-3.4nm,C-20nm
C. A-3.4Å,B-3.4Å, C-20Å
D. A-34 Å,B-3.4Å , C-2Å

Answer

a

Explanation

(a) : The DNA helix makes one complete spiral turn every 3.4 nm and has a diameter of 2 nm. The distance between adjacent stacks is `0.34`nm.