Im not sure but I think it was the beginning of modern warfare.
The event you're describing is called the Ra pe of Nanking. It happened in 1937. Around 50,000 innocent Chinese people were killed by Japanese troops.
Answer:
They opposed the European colonization.
Explanation:
The Europeans invaded, raided, explored, and sometimes even enslaved the native people from the lands that they colonized. There's no way that such a behavior was seen as something good and people did not like at all what was happening to them and to their lands.
I believe the the answer is C. A difficult journey to get there.
I hope this helps!
