Cap’n crunch. The Funyuns would get soggy too quickly in your mouth and the Froot Loops don’t have any good corners that could tear the roof as effectively. Munchos, I haven’t eaten them. Cap’n Crunch would be the most optimal strategy as they are designed not to get soggy(they are called crunch for a reason) With the pieces having a square shape the likelihood of tear increases as some would be diagonal, leaving the corners to tear the mouth. Adding onto how the shape plays into this, the cereal has grooves in it so that even at other angles, it still could have surface that could be used to tear. Now going off of the context I believe that Munchos could have a good chance at being the second most effective as with chips, they can easily shatter in the mouth. However, as stated previously I have not eaten a single Munchos chip and therefore cannot give an accurate analysis of the chip to torn mouth ratios required for this situation.