What Is One Difference Between the Recently Developed Technique Known

Multiple Choice

What is one difference between the recently developed technique known as CRISPR/Cas9, and a (gene) knockout procedure?

A) CRISPR/Cas9 can remove genes, whereas knockout procedures can only add them.
B) In theory, CRISPR/Cas9 can be applied to humans, whereas knockout procedures cannot.
C) CRISPR/Cas9 is far slower and less inefficient than knockout procedures.
D) CRISPR/Cas9 can both remove and add genes, whereas knockout procedures can only remove them.
E) In theory, knockout procedures can be applied to humans, whereas CRISPR/Cas9 cannot.