Drug P is the original patented drug product. Drugs X, Y, and Z are generic drug products to Drug P. The Orange Book classifies Drug X as A rated to Drug P. It classifies Drugs Y and Z as B rated to Drug P. Which statement is correct?
1) Drugs X, Y, and Z are therapeutically equivalent to Drug P.
2) Drugs Y and Z are therapeutically equivalent to one another.
3) Drugs P and X are therapeutically equivalent to one another.
4) Drugs Y and Z are therapeutically equivalent, and Drugs P and X are therapeutically equivalent.
