I had to google "butterfly" and "eagle" sex positions before I could answer. lol
Who knew?! Turns out the butterfly and eagle are two of my favorite positions.
I chose missionary on the poll because "butterfly" and "eagle" are just fancy names given to positions that fall under the general header of "modified missionary". In fact, one website depicted the butterfly as a position called "butterfly or modified missionary". Another website showed the same position as the "downstroke" while depicting the butterfly with the man kneeling bedside with the woman's feet touching the floor - very confusing to say the least!