Final answer:
An interview with a nutritionist who describes the benefits of healthy school lunches would offer the most credible support for healthy school lunch options.
Step-by-step explanation:
The best piece of evidence to support an argument in favor of healthy school lunch options would be (d) An interview with a nutritionist who describes the benefits of healthy school lunches. This is because a nutritionist is a trained professional who can provide credible information on how healthy food choices can impact the growth, development, and overall health of students. Evidence from a nutritionist can link the importance of healthy eating to a child's education and well-being, reinforcing the argument for nutritious meals at school.