Final answer:
The correct statement showing understanding of dietary precautions is to avoid foods that could be potential sources of bacteria, which is critical for patients undergoing chemotherapy.
Step-by-step explanation:
A patient who has cancer and is receiving chemotherapy needs to be especially cautious about dietary choices due to a potentially weakened immune system. Among the provided options, the statement that indicates an understanding of the dietary teaching to reduce the risk of infection is: "I'll avoid foods that are potential sources of bacteria." This reflects the advice that patients undergoing chemotherapy should avoid foods like raw or undercooked poultry or meat, unpasteurized milk or juice, cheese, and raw fruits and vegetables which could be contaminated with harmful pathogens. Raw food diets and consumption of undercooked meats or unpasteurized dairy products would increase the risk of infection.