The correct answer is They are binding legal agreements.
That means that if you sign and you haven't read it and you find something that you don't like later, you can't choose to not do it. It is not required but should always be done.
The answers is D because all of the other choices are unrelated to the question.
Marta is the subject of the sentence because she is performing the verb "Planned"
It would be about them not winning
