The table shows data Chargaff collected on DNA nitrogenous bases in five organisms. Percentages of Bases in Five Organisms
Source of DNA A T G C
Streptococcus 29.8 31.6 20.5 18.0
Yeast 31.3 32.9 18.7 17.1
Herring 27.8 27.5 22.2 22.6
Human 30.9 29.4 19.9 19.8
E. coli 24.7 23.6 26.0 25.7

Which statement did Chargaff conclude based on these data? Note that a letter in brackets, such as [A] or [C], refers to the concentration of one of the nitrogenous bases.
A. in DNA molecules, [T] > [A] > [G] > [C]
B. in DNA molecules [A] = [G], and [C ] = [T]
C. in DNA molecules, [A] = [T], and [C ] = [G]
D. in single-stranded DNA molecules, [A] = [T] = [C ] = [G]