You leave out so many choices.
Mine would be "Rationalist."
But, since such a wonderful answer is not among your choices, I must choose "Believer."
I believe in the human spirit. I believe we can overcome religion and superstition. I believe we humans are genetically one family that comes from a common female ancestor called by many, Mitochondrial Eve, who could have lived 200,000 years or so ago, along with a common male ancestor, Y-chromosomal Adam, who could have lived between 142,000 and 60,000 years ago. (Records would have no way of knowing in this emerging science so the exact time has not been nailed down- the point is that we are all related.)
I believe that false beliefs will all be disguarded eventually, including any belief in any of the current "gods" that man has created. Unluckily for us, I also believe that new false beliefs will spring up to replace Zeus, Jehovah, Christ, and the like, and these must also run their courses.
Here's a few more things that I believe (understanding that poetic liscence has taken place and I might not "literally" believe the exact statements, but the idea behind them, similarly to belief in the Bible which is already proven totally false):
I believe, for every drop of rain that falls,
A flower grows.
I believe that somewhere in the darkest night,
A candle glows.
I believe for everyone who goes astray,
Someone will come, to show the way,
I believe, I believe.
I believe, above the storm the smallest prayer,
Will still be heard.
I believe, that someone in the great somewhere,
Hears every word.
Everytime I hear a newborn baby cry,
Or touch a leaf, or see the sky,
Then I know why, I believe!
I also believe:
I believe I can fly
I believe I can touch the sky
I believe in music
I believe rock and roll can save your mortal soul
I believe in love
Most of all, I believe in you.