I'd say probably the cheese pizza will be less in calories, assuming a thin-crust pizza. Honestly in this situation I'd probably pick the one that seems most tasty (which to me would be the bbq chicken). I'd feel deprived with a slice of cheese pizza if other tasty offerings are available. Especially if I have the discipline to limit myself to one piece! One slice of heartily enjoyed pizza isn't going to make or break my eating habits over the long term. If it's a deep dish or thicker crust style pizza, I might just eat the top of the pie with a fork and leave the crust. Another thing to do is to sop up the grease that collects on top of the cheese before eating it. It's a bit fewer calories, plus a little neater to eat.
Have fun & enjoy!
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