Correct Answer: B

Rationale: The correct answer is B: Insect. A vehicle transmission refers to the mode by which a disease spreads from one host to another. Insects can transmit diseases, making them a vehicle for transmission. Airborne, foodborne, and bodily fluid transmissions are well-known modes of disease spread, while insects are also known vectors for diseases like malaria and Zika.

Correct Answer: B

Rationale: The correct answer is B: scalp. Tinea capitis is a fungal infection that specifically affects the scalp. This infection is caused by dermatophytes, which thrive in warm and moist environments. It typically presents with symptoms such as scaling, itching, and hair loss on the scalp. Choices A, C, and D are incorrect because tinea pedis (athlete's foot) affects the feet, oral thrush is a fungal infection of the mouth, and tinea manuum affects the hands. By process of elimination and understanding the specific characteristics of tinea capitis, we can determine that the scalp is the correct location for this fungal infection.

Correct Answer: B

Rationale: The correct answer is B: Insect. A vehicle transmission refers to the mode by which a disease spreads from one host to another. Insects can transmit diseases, making them a vehicle for transmission. Airborne, foodborne, and bodily fluid transmissions are well-known modes of disease spread, while insects are also known vectors for diseases like malaria and Zika.

Correct Answer: A

Rationale: The correct answer is A: Burri-Gins. This staining method specifically targets the detection of capsules in bacteria. It involves staining the capsules with crystal violet and the background with safranin. This staining technique helps visualize the capsules as a distinct halo around the bacteria. Summary: - Choice B (Ziehl-Neelsen) is used for acid-fast staining to detect Mycobacterium species. - Choice C (Neisser) is used for staining Neisseria species. - Choice D (Gram) is a common staining method used to differentiate bacteria based on cell wall composition (Gram-positive and Gram-negative), but it does not specifically target capsules.

Correct Answer: A

Rationale: The correct answer is A: Clostridium perfringens. Gas gangrene is caused by Clostridium perfringens, a Gram-positive rod bacterium that produces spores. This bacterium is anaerobic and commonly found in soil, where it forms spores that can survive harsh conditions. Clostridium tetani causes tetanus, not gas gangrene. Bacillus anthracis causes anthrax, not gas gangrene. Clostridium botulinum causes botulism, not gas gangrene. Therefore, based on the characteristics of the microorganism described in the question, Clostridium perfringens is the correct identification.