Related Questions
Correct Answer is D
Explanation
Choice A Reason: This is incorrect because mosquitoes do not transmit HIV. HIV is a virus that infects human cells and cannot survive in insects. Mosquitoes do not inject blood from one person to another when they bite, but only saliva that contains anticoagulants and enzymes.
Choice B Reason: This is incorrect because accidental puncture wounds are not a common mode of HIV transmission. HIV can be transmitted through exposure to infected blood or body fluids, such as through needle sharing, blood transfusion, or occupational injury. However, these cases are rare and can be prevented by using sterile equipment, screening blood products, and following universal precautions.
Choice C Reason: This is incorrect because casual contact is not a mode of HIV transmission. HIV is not an airborne virus and cannot be spread by coughing, sneezing, or breathing. HIV cannot be transmitted by hugging, kissing, or sharing utensils.
Choice D Reason: This is correct because direct contact with infected body fluids is the most common mode of HIV transmission. HIV can be transmitted through unprotected vaginal, anal, or oral sex with an infected person, as these activities can involve contact with infected blood, semen, vaginal fluid, or pre-ejaculate. HIV can also be transmitted through sharing needles or syringes with an infected person, or from mother to child during pregnancy, childbirth, or breastfeeding.

Correct Answer is B
Explanation
Choice A Reason: This is incorrect because marijuana is a psychoactive substance that affects the central nervous system and can cause euphoria, relaxation, altered perception, and impaired memory. It does not cause tachycardia, hypertension, or vasoconstriction in pregnant women or their fetuses.
Choice B Reason: This is correct because cocaine is a stimulant substance that affects the cardiovascular system and can cause tachycardia, hypertension, vasoconstriction, arrhythmias, and ischemia in pregnant women or their fetuses. It can also increase the risk of placental abruption, preterm labor, intrauterine growth restriction, and fetal death.
Choice C Reason: This is incorrect because nicotine is a stimulant substance that affects the respiratory system and can cause bronchodilation, increased heart rate, and increased blood pressure in pregnant women or their fetuses. However, it does not cause vasoconstriction, but rather vasodilation.
Choice D Reason: This is incorrect because caffeine is a stimulant substance that affects the central nervous system and can cause alertness, insomnia, anxiety, and increased urine output in pregnant women or their fetuses. It does not cause tachycardia, hypertension, or vasoconstriction in moderate doses.
Choice E Reason: This is incorrect because heroin is an opioid substance that affects the central nervous system and can cause euphoria, sedation, analgesia, and respiratory depression in pregnant women or their fetuses. It does not cause tachycardia, hypertension, or vasoconstriction.

