I believe your answer is B. ( not sure of any others) hope i helped! :)
As you didn't specify what exactly is required, I am guessing the correct answer that is requested here is - Charlemagne was able to bring together and unit a big portion of Western Europe during the early middle ages under one banner. This is his most known achievement, or at least the one that is most talked about. Furthermore, doing this he helped lay out the foundations for countries that would be later known as France and Germany :)
To prevent damage to the outboard boat that is going to be towed, it is a priority and what should always do is to raise the engine. Raising the engine could prevent damage and it is also essential to secure it. So that it wouldn't be exposed and to prevent it from being harm or damage, leading to serious mechanical issues.
C social learning, because they are imitating what they learned from television
