Answer;
-Malachite green
Explanation;
-Malachite green is also used in endospore staining, since it can directly stain endospores within bacterial cells; here a safranin counterstain is often used.
-Because of their tough protein coats made of keratin, spores are highly resistant to normal staining procedures. The primary stain in the endospore stain procedure, malachite green, is driven into the cells with heat.
The answers are stress accumulations and reoccurrence! I hope this helped you and I hope you have a great day! :)