Correct Answer: C

Rationale: The patient is likely infected with Cryptosporidium parvum based on the symptoms of watery diarrhea, abdominal cramps, and nausea after consuming contaminated water. Cryptosporidium is a protozoan parasite that can be transmitted through contaminated water sources, such as streams. Laboratory tests revealing oocysts in the stool sample further support the diagnosis of Cryptosporidium infection, as these oocysts are characteristic of this parasite. Giardia lamblia is another common protozoan parasite that can cause similar symptoms but is usually associated with more foul-smelling, greasy diarrhea. Entamoeba histolytica causes amoebic dysentery, which presents with bloody diarrhea and abdominal pain. Cyclospora cayetanensis also causes watery diarrhea, but it is usually associated with foodborne outbreaks rather than waterborne transmission.

Correct Answer: B

Rationale: The symptoms described in the patient, such as tremors, rigidity, bradykinesia (slow movement), and postural instability, along with the presence of a shuffling gait, stooped posture, and masked facies, are classic features of Parkinson's disease. These motor symptoms are primarily caused by the degeneration of dopamine-producing neurons in the substantia nigra region of the brain. This results in an imbalance of neurotransmitters, particularly dopamine, leading to motor dysfunction and characteristic movement abnormalities seen in Parkinson's disease.

Correct Answer: D

Rationale: The correct action to prioritize during the initial assessment when preparing to assist with a cardiopulmonary resuscitation (CPR) procedure for a patient in cardiac arrest is to assess the patient's airway, breathing, and circulation (ABCs). This involves quickly checking the patient's airway for any obstructions, assessing their breathing for signs of breathing difficulties or absence of breathing, and evaluating their circulation by checking for a pulse. This step is crucial in determining the need for immediate intervention, such as clearing the airway, providing rescue breaths, or initiating chest compressions. By prioritizing the assessment of the ABCs, the nurse can promptly identify and address life-threatening issues to improve the patient's chances of survival during a cardiac arrest situation.

Correct Answer: C

Rationale: Humoral immunity is primarily responsible for protecting against infections by pathogens like viruses. In the case of the hepatitis B virus (HBV), the individual is exposed to the virus and develops immunity, which is typically mediated by antibodies produced by B cells. These antibodies circulate in the blood and can neutralize the virus, preventing future infections. This type of immunity is known as humoral immunity, as it involves the production of antibodies that target specific antigens, such as those present on the surface of the hepatitis B virus. In contrast, passive immunity is when antibodies are transferred from an external source, innate immunity provides immediate, non-specific defenses against pathogens, and cell-mediated immunity involves the activation of T cells to combat intracellular pathogens.

Correct Answer: C

Rationale: Verbal abuse is the most common form of abuse experienced by nurses in their workplace. This may include insults, yelling, threats, or intimidation directed towards the nurse. Verbal abuse can have a significant impact on the nurse's mental and emotional well-being, leading to stress, anxiety, and burnout. It is important for healthcare institutions to address and prevent verbal abuse to create a safe and respectful work environment for nurses and other healthcare professionals.