Margaret is a graduate student that studies root architecture in the model organism Arabidopsis thaliana. She has fixed and stained a mutant and a wild-type root with a non-fluorescent dye that adheres to the cell wall and would like to visualize the stained whole roots under the microscope. Which of the following microscopes should Margaret use to analyze her samples?
A. A light microscope B. A fluorescent microscope C. A scanning electron microscope D. An electron microscope