1. **State the problem:** We need to find the probability that a randomly chosen camper is a 13-year-old boy. 2. **Recall the probability formula:** $$\text{Probability} = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}}$$ 3. **Identify the favorable outcomes:** The number of 13-year-old boys is 12. 4. **Identify the total outcomes:** The total number of campers is 80. 5. **Calculate the probability:** $$\text{Probability} = \frac{12}{80}$$ 6. **Simplify the fraction:** $$\frac{12}{80} = \frac{\cancel{4} \times 3}{\cancel{4} \times 20} = \frac{3}{20}$$ 7. **Convert to decimal:** $$\frac{3}{20} = 0.15$$ **Final answer:** The probability that the camper chosen is a 13-year-old boy is **0.15**. This corresponds to option D.