Correct Answer: A

Rationale: Colony-stimulating factors are substances that stimulate the production of blood cells in the bone marrow. Erythrocytes are red blood cells, so a colony-stimulating factor would specifically stimulate the growth of red blood cells, leading to an increase in the patient's erythrocyte count. Choice B is incorrect because colony-stimulating factors do not suppress T-cell production. Choice C is incorrect because colony-stimulating factors do not inhibit protein synthesis. Choice D is incorrect because colony-stimulating factors do not stimulate antibody production; they primarily affect the production of blood cells.

Correct Answer: C

Rationale: The correct answer is to use the Wong-Baker FACES scale to assess the child's pain. This scale is specifically designed for children and uses facial expressions of varying intensities to help them communicate their pain levels effectively. Choices A and B may not be as suitable for a young child who may have difficulty understanding or using a numerical scale. Choice D involving parents may not provide an accurate reflection of the child's pain experience, as it is essential to assess the child's self-reporting.

Correct Answer: C

Rationale: Ivermectin (Stromectol) is commonly used to treat parasitic infections, particularly Strongyloides stercoralis. This parasitic infection is known to respond well to Ivermectin therapy. Entamoeba histolytica causes amoebiasis and is typically treated with antiprotozoal drugs like metronidazole, not Ivermectin. Giardia lamblia is a protozoan parasite causing giardiasis, which is usually treated with medications like metronidazole or tinidazole, not Ivermectin. Plasmodium falciparum is a malaria-causing parasite and is not treated with Ivermectin but with antimalarial medications like chloroquine or artemisinin-based combination therapies.

Correct Answer: A

Rationale: An attenuated antigen used in a vaccine is alive but less infectious, aiming to stimulate an immune response. Choice B is incorrect because an attenuated antigen is not highly infectious. Choice C is incorrect as the antigen is intentionally altered to be less infectious. Choice D is incorrect as an attenuated antigen is not infectious.

Correct Answer: C

Rationale: The correct answer is C. Oral contraceptives can be less effective when taken with certain antibiotics due to potential drug interactions that may reduce contraceptive efficacy. It is crucial for patients to be aware of this to consider additional contraceptive measures when prescribed antibiotics. Choice A is incorrect because while oral contraceptives are highly effective when taken correctly, they are not 100% foolproof. Choice B is incorrect as oral contraceptives may take some time to reach their full effectiveness after starting. Choice D is also incorrect as taking oral contraceptives with food does not significantly affect their efficacy.