Correct Answer: C

Rationale: The correct answer is C: Vibrio. Cholera is caused by Vibrio cholerae bacteria. These bacteria produce a toxin that causes severe diarrhea and dehydration. Escherichia (choice A) and Salmonella (choice B) are known for causing other types of gastrointestinal infections but not cholera. Acinetobacter (choice D) typically causes respiratory infections, not gastrointestinal illnesses like cholera. Therefore, the correct choice is Vibrio as it is specifically associated with cholera.

Correct Answer: D

Rationale: Rationale: - A: The mycelium is indeed made up of intertwined hyphae, which are the branching filaments of fungi. - B: Part of the mycelium does grow into the medium to acquire nutrients, forming the substrate mycelium. - C: Some parts of the mycelium remain above the medium to aid in reproduction and spore dispersal, forming the aerial mycelium. Therefore, all statements (A, B, and C) are correct, making choice D the correct answer. The mycelium exhibits both intertwined hyphae, substrate mycelium, and aerial mycelium to facilitate different functions.

Correct Answer: D

Rationale: Rationale: 1. Mycobacterium tuberculosis, Legionella pneumophila, Brucella melitensis can evade complete phagocytosis. 2. Mycobacterium tuberculosis inhibits phagosome-lysosome fusion. 3. Legionella pneumophila can prevent phagosome maturation. 4. Brucella melitensis can survive and replicate within phagocytes. 5. A + B + C together represent non-complete phagocytosis. Summary: - A, B, C individually cause incomplete phagocytosis. - Only when all three are present together (D) is non-complete phagocytosis observed.

Correct Answer: A

Rationale: The correct answer is A: Dysenteric amoeba. This is because dysenteric amoebas can cause asymptomatic parasitosis, where a healthy person carries cysts that can infect others. Dysenteric amoebas are known to infect the intestines and can be transmitted through contaminated food or water. Choice B, Malarial plasmodium, causes malaria transmitted through mosquitoes. Choice C, Enteral trichomonad, causes diarrhea and is transmitted through contaminated water. Choice D, Dermatotropic leishmania, causes skin lesions and is transmitted through sandfly bites. These choices do not fit the scenario of asymptomatic parasitosis in public catering establishments.

Correct Answer: A

Rationale: The correct answer is A: Amebiasis. Amebiasis is caused by the parasite Entamoeba histolytica, presenting with symptoms like acute abdominal pain, bloody diarrhea with mucus, and inconstant shape organisms seen in fecal smear. The presence of erythrocytes supports the diagnosis due to the parasite's ability to invade intestinal mucosa causing bleeding. Choice B (Lambliasis) presents with different symptoms like steatorrhea and fatigue. Choice C (Schistosomiasis) is mainly associated with liver and urinary symptoms. Choice D (Intestinal trichomoniasis) commonly presents with watery diarrhea and does not typically cause bloody stools. Therefore, based on the patient's symptoms and fecal smear findings, Amebiasis is the most likely diagnosis.