This question is also really stupid:

One parent can bring up a child as well as two parents together.

Can? Sure. One good parent can do a better job than two shitty parents. On the whole, taking averages, children with two parents will benefit from having two parents in all kinds of ways. So will a child with involved grandparents. So what way should I answer? And why would acknowledging the reality that two ideal parents are better than one ideal parent make me ‘republican’? I don’t see why it matters in the least.