Just shows a timeline from 1820 to 1920
For how many years were tensions between European nations growing before World War I finally broke out?
A 19 years
B 50 years
C 45 years
D 15 years
![Just shows a timeline from 1820 to 1920 For how many years were tensions between European nations growing before World War I finally broke out A 19 years B 50 y class=](https://us-static.z-dn.net/files/d29/3a827a74d6fa995744d682068dead4d6.jpg)