Final answer:
We cannot determine the percentage of dog skin infections that successfully resolved without a second injection based on the information provided.
Step-by-step explanation:
The question is asking about the percentage of dog skin infections that successfully resolved without a second injection in field studies. The answer choices are A) Less than 50%, B) 50-75%, and C) More than 75%. Based on the information provided, we do not have specific data on the percentage of successful resolutions without a second injection, so we cannot determine which answer choice is correct.