How Successful Was the Portuguese Monopoly on Asian Products

How successful was the Portuguese monopoly on Asian products?

A) For some decades they were able to maintain a complete monopoly over Asian products shipped to Europe.
B) Though they managed to monopolize some spices grown in limited locales, the Portuguese lacked the manpower and ships to sustain a monopoly.
C) The Portuguese were unable to achieve control over any Asian products due to competition from the Chinese commercial navy.
D) The Portuguese monopoly was rigidly enforced over Asian products for almost two centuries.