In 13th century Hungary, the Mongal invasions caused ...

A. Attacks from the Ottoman Turks

B. Widespread destruction

C. a strong Hungarian monarchy

D. the spread of Roman Catholicism

I would say that the best answer here is B. A widespread destruction.

Perhaps another consequence is a change in building habits in Hungary: the castles after the invasion were made more sturdy

Ps. The Ottomans came only around 16th century