What Is the Principal Reason That the FDA Has Banned

What is the principal reason that the FDA has banned the sale of products containing ephedrine?

A) The costs are prohibitive.
B) The products were found to be ineffective for weight loss.
C) The products were implicated in several cases of heart attacks and seizures.
D) The products were found to contain contaminants that were believed to be responsible for inducing liver failure.
E) They were contaminated with substances that induced a Parkinson-like syndrome.