I’m pretty sure it’s B but I could be wrong
I hope this is helpful but sorry if it isn’t
One thing that happened during the Crusaders was a temporary unification of muslim forces under the banner of a famous general called Saladin. He unified muslim forces which were fighting each other (most notably Seljuk Turks with their minor skirmishes before the First Crusade) and managed to create one united muslim force.
Protecting the right to vote is super important because the people need to have a say in something

This sentence gives no reason to add any commas what so ever. This would be a straight forward run-on sentence that would need no clause, pauses or anything that would break this sentence down any more.
Option B would give clear and straight forward information. The first option broke this sentence down as we can see, and as for this, this would not be the proper way of expressing this sentence. Therefore, your
last option would then be your answer.