The posed question,

"So far in this lab, you have used one type of simple stain (crystal violet) and one type of negative stain (Nigrosin), yet there are many other simple and negative dyes available. Pick one simple dye and one negative dye, and discuss how those dyes differ from the ones you used in this lab. Give a scenario in which their use would be appropriate."

I had picked methylene blue and india ink as my two stains to discuss.