Alright, let's break this down. From left to right we have: Blonde #1, Brunette #1, Ginger, Blonde #2, Creepy Smile, Brunette #2, Blonde #3, Asian, Blonde #4, and Hispanic. So let's first eliminate some of the ones we know it can't be. Studies have shown that each ethnicity will stick to their own (whites will look for whites, asians for asians, etc) (Source: Freakonomics). If we are to follow modern stereotypes, we know that Asians lack in length and Hispanics, while average in length (maybe a little less) have more girth. So we can assume that the Asian and Hispanic have more experience with their respective races, and therefore would not be able to handle an XL, as it were. Next, we can clearly see that both bottled and canned beer are being served at this party. If we are to follow TV psychology, anything phallic is a substitute for a penis. So we can eliminate Blonde #2 and Blonde #3 as they are holding cans. While they may still be whores, they are probably not a fan of holding a penis in their hand. Next, we observe the gigantic smiles that reveal some giant chompers on Creepy Smile and Blonde #4. Evolution has taught us that all features are evolved for a reason. Big teeth would have been developed for large (or in this case, very girthy) specimens, showing the preference of their mothers. As the saying goes "like mother like daughter", so their preference would be girth over length. Once again, not very helpful in a Deep Throat Competition. This leaves us with Blonde #1, Brunette #1, Ginger, and Brunette #2. As we can see from the way Brunette #2 dresses, she clearly has put on her "No one is touching me tonight" dress, as shown by the obvious lack of cleavage and push-up bra. While it could be that she chose to dress conservative just tonight, you do not attend a "Deep Throat Competition" party dressed up like a nun. Similarly, as can be seen from Brunette #1's awkward smile, she doesn't look like she wants to be here. She was probably one of those friends that got dragged along to be the DD (designated driver you perverts). This leaves us with Blonde #1 and Ginger. Now you may lean towards the blonde as she is hotter so you would expect her to have more experience, but if you look at the way they are holding their beer bottles, the answer is blatantly clear. Blonde #1 is literally choking her beer bottle. Now ask yourself this, would you like someone to choke your penis? Like squeeze on it until it burst? I didn't think so. Whereas you can clearly see the Ginger has a loose, but firm grip on her beer bottle, showing she clearly knows what she's doing. So based on a process of elimination, as well as most likelihood of having given the most head. I posit that the Ginger is the reigning Deep Throat Champion.