Which of the following is INCORRECT according to the news item？A．A quarter of medicines so

Which of the following is INCORRECT according to the news item？

A．A quarter of medicines sold in poor countries are fake.

B．Half of drugs available in some African and South American countries are fake.

C．Stricter regulation and better international collaboration are needed to check fake medicines.

D．The circulation of fake or substandard medicines leads to frequent treatment failure.

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