Which river passes through maximum number of countries?

A. Mississippi
B. Amazon
C. Yangtze
D. Danube

The Danube river in Europe is the river that passes through the maximum number of countries in its journey.
It passes through 10 countries: Germany, Hungary, Romania, Austria, Serbia, Bulgaria, Croatia, Moldova, Ukraine, Slovakia.
It starts in Southern Germany and runs into the Black Sea through Romania.
It is the second-longest river in Europe after the Volga with a length of 2,850 kilometres.