The answer is option C "Being an active listener." It's not option A because refusing to cooperate is refusing to listen to your spouse which is a bad component in a relationship. It's not option B because letting your spouse set your boundaries for you is mainly meaning that she's telling you what to do which is a controlling relationship, it's also not option D because agreeing to a compromise is another way to solve a problem or a argument and never doing that is not safe. So it's option C because the other options are examples of a bad relationship.
Hope this helps!
~Nonportrit