A specific and testable question you could ask about the genetics of pink and white peony flowers might be: "What is the genetic basis for flower color variation in peony plants, and how does it relate to the expression of specific genes?"
To test this question, you could conduct experiments to isolate and analyze the DNA of both pink and white peony plants, looking for differences in the expression of genes known to be involved in flower pigmentation. You could also perform crosses between pink and white plants to see if the offspring show intermediate or predictable patterns of color expression, and examine the inheritance patterns of flower color in successive generations. By comparing the DNA and phenotype of the plants, you could gain insights into the genetic basis for flower color variation in peony plants.