Correct Answer: D

Rationale: The correct answer is D: rabbit fever. Tularemia is commonly known as rabbit fever due to the fact that it is often contracted through handling infected rabbits or other rodents. This zoonotic disease is caused by the bacterium Francisella tularensis. Scarlet fever (
A) is a streptococcal infection characterized by a rash, not related to tularemia. Strep throat (
B) is a bacterial infection caused by Streptococcus bacteria and is not associated with tularemia. Cat scratch fever (
C) is caused by Bartonella henselae and typically transmitted through cat scratches or bites, not related to tularemia.

Correct Answer: A

Rationale: The correct answer is A: Gram staining. This method is used to differentiate bacteria based on their cell wall composition. In cholera, the causative agent is Vibrio cholerae, which is Gram-negative. By performing Gram staining, the bacteria will appear pink/red under the microscope, confirming the presence of Gram-negative bacteria.


Choice B: Neisser's staining is used for staining capsules of bacteria, not suitable for confirming cholera diagnosis.


Choice C: Ziehl-Neelsen staining is used for acid-fast bacteria like Mycobacterium tuberculosis, not for confirming cholera diagnosis.


Choice D: Burri-Gins staining is not a standard staining method in microbiology and is not relevant for confirming cholera diagnosis.

Correct Answer: D

Rationale: The correct answer is D: Tuberculosis. Tuberculosis is considered a reemerging disease due to the increase in drug-resistant strains, high global prevalence, and challenges in diagnosis and treatment. This is supported by global health organizations' reports on the resurgence of TB cases.

A: AIDS is not considered a reemerging disease as there has been significant progress in HIV prevention and treatment.

B: Ebola outbreaks are sporadic and localized, not considered reemerging on a global scale.

C: West Nile virus outbreaks occur periodically, but it is not considered a reemerging disease compared to TB.

Correct Answer: A

Rationale: The correct answer is A: Entamoeba gingivalis. This organism matches the description provided in the question - unicellular with pseudopodia and ingested white blood cells, commonly found in dental plaque. Entamoeba gingivalis is known to inhabit the oral cavity and is associated with periodontal disease. Trichomonas vaginalis, Giardia lamblia, and Balantidium coli do not match the characteristics mentioned in the question and are not typically found in the oral cavity.

Correct Answer: B

Rationale: Fimbriae in bacteria are hair-like appendages that help in adhesion to surfaces. This is essential for colonization and infection. Fimbriae do not provide motility (flagella do), facilitate protein synthesis (ribosomes do), or help in endospore formation (specialized structures do). Adhesion is the primary function of fimbriae, allowing bacteria to stick to host cells or abiotic surfaces.