Which of the following statements about the 5' end of a polynucleotide strand of DNA is correct?

A)The 5' end has a hydroxyl group attached to the number 5 carbon of ribose.
B)The 5' end has a phosphate group attached to the number 5 carbon of ribose.
C)The 5' end has phosphate attached to the number 5 carbon of the nitrogenous base.
D)The 5' end has a carboxyl group attached to the number 5 carbon of ribose.
E)The 5' end is the fifth position on one of the nitrogenous bases.