Spotting

I will defer to my esteemed colleague and classify this as the original suggestion.

I do not see any indications of a dorsolateral fold. There is a ridge that borders the tympanum, which both Green frogs and Bullfrogs have. The dorsolateral fold that Greens frogs have are very obvious, especially on light individuals like this one.

I'm going to suggest a green frog because this appears to have a dorsolateral ridge. It's not entirely clear from the picture but I believe it's there. Bullfrogs lack this feature.

This is definitely a Bullfrog. Green frogs have a dorsolateral fold, and Bullfrogs do not. The frog pictured here does not have that fold.