Since you have not provided the choices, I will just provide you with some of Charlemagne accomplishments and hopefully they will help you choose the correct choice from the ones you have.
Charlemagne:
1- He encouraged a revival of learning within his empire
2- preserved law and order
3- preserved a strong government
4- reunited large areas of the Western Roman Empire
It is good to notice that Charlemagne did not succeed in driving the Muslims out of North Africa.