Discussion
The idea behind picking C is that you are looking at it as a benefit for the individual doing the volunteering.
Consider Brainly. Why do people answer questions on Brainly. Is C true for them? It really isn't. They answer questions because they confirm how and why they think their answer is true. Nothing is true if it cannot be well explained.
And yet, we have to ask if it is civic when a question is answered. I think it is. Through the miracle of the internet, we are participating world wide. Our community is not the place where we live. We are connected by the technology we use. The world is our community. But it is still impersonal.
That is the yes part of C. But the no part has a place as well. There is still that overhang when you look at C. It is too much like "What's in it for me?" I never ask that question on Brainly. I'm not a student, but I still must confirm what I think, especially with a question like this one.
Don't be fooled. A has it's set of strengths and weaknesses too. A is your choice. Stick with it. Multiple Choice questions can be dreadful. This one just happens to fall into that category.
If it is any consolation to you, I think that the intended answer is C, but it has flaws.