It makes them more independent. If they had a limitless amount of terms, they could just vote for whatever was suitable at that time and keep their political power. Since they won't be able to stay in the congress longer, then they can vote whatever they want because there's nothing that will affect whether or not they get elected again.
I think you should double check it and see if you can find the answer if not come back and ask again
<em>It's A, Protects people's ideas</em>
4. <span>Formal </span><u>adoption</u> of the Declaration of Independence in 1776 by <span>Continental Congress.</span>