Final answer:
Option C is the most concise revision because it succinctly captures the essential drawbacks of regular junk food consumption, including low nutritional content and excess calories.
Step-by-step explanation:
The most concise revision of the passage is option C: Junk food is not ideal for regular consumption because it has little nutritional content and excessive calories, which may lead to health issues. This revision summarizes the drawbacks of regular consumption of junk food by mentioning the lack of essential nutrients and the presence of excessive calories that can contribute to health problems. These factors are important because junk food is often high in energy density but low in nutrient density, which can result in unbalanced nutrition and increase the risk for chronic diseases such as heart disease, diabetes, and obesity.