Which of the following statements is INCORRECT according to the passage？A．In Great Britain

Which of the following statements is INCORRECT according to the passage？

A．In Great Britain, Valentine"s Day began to be popularly celebrated around the 17th century.

B．Americans probably began exchanging hand-made valentines in the early 1800s.

C．The oldest known valentine still in existence today was a poem written by Duke of Orleans.

D．Valentine was one of the most popular saints in England and France in the Middle Ages.

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