Really?  Seriously  according to OK Cupid's analysis of their data from asking 642533 people the question  5% of men (gay and straight) and 10% of women (gay and straight) think the Earth is bigger than the Sun.  This finding is in a posting by Ok Cupids researchers about gay Vs straight sex. 
 The earth or the sun?

Ok, I suppose we can argue about just what one means by "bigger".  The only way that that percentage of people are not even wrong is if we say the Sun looks smaller in the sky than the Earth beneath us which is obviously huge.    That is the only defense for that answer.  

That many people don't get a basic question of logic, astronomy and physics correct leaves me utterly speechless.    

If anyone wonders why various bits of pseudo science can find a following among the unwashed masses they need look no father than to the minds that cannot answer such a basic question. 

In case anyone needs it explained...the correct answer is that the sun is bigger.  It has many times greater mass, and volume than the Earth.    It's apparent size in the sky not withstanding the Sun is bigger than the Earth in every way.