How did the actions of Emperor Diocletian contribute to the decline of the Roman Empire?
A. By dissolving the Senate, he caused a popular uprising in the imperial capital of Rome.
B. By splitting the empire in two, he left the Western Roman Empire vulnerable to invasion.
C. By pursuing a policy of expansion through conquest, he bankrupted the Roman Empire.
D. By opening Rome's borders to traders, he enabled the plague to spread in the Roman Empire.