There is a biohazardous bag usually included with other PPE kit package, Why this?

Anurse is teaching a client who has a new prescription for nitroglycerin patches. the nurse should identify which of the following statements as an indication that the client understands the teaching? a. “i will move the patch to my leg if i get a headache.” b. “i will rotate the application site to avoid skin irritation.” c. “i will apply a new patch if i have chest pain.” d. “i cannot take a sublingual tablet of nitroglycerin after applying the patch.”