Answer:
Option C, unintended and often undesirable effects of the medication
Explanation:
In pharmacology, side effects of medications are the phenomena following administration that a certain drug or class of drugs are known to cause, outside of what the medication is expected to produce according to the medication's indication.
In lay terms, the drug does what it is supposed to do, but also may do something else in the process.
For example, the laxative medication lactulose softens stool by increasing water content within the bowels, thereby making the passage of feces easier and providing relief in patients experiencing constipation. In doing so, the fecal content can loosen to the point where the patient is passing diarrhea. Because this is known by healthcare providers and the manufacturers of lactulose, it is listed as a side effect. Because the medication recruits water to the bowels, they may also experience some abdominal distension or bloating.
Side effects are unintended and often undesirable effects of a medication, option C.