HIV Transmission Pathways

Steps:

• Recall HIV spreads via specific bodily fluids containing the virus, not casual contact.
• Identify transmission routes: blood (e.g., shared needles), semen (e.g., unprotected sex), but not air or saliva.
• Eliminate options allowing air transmission, as HIV isn't airborne.
• Confirm D matches: no air, yes blood, no saliva, yes semen.

Why D is correct:

• HIV transmits through infected blood and semen per CDC guidelines, but not air (not airborne) or saliva (insufficient virus concentration).

Why the others are wrong:

• A: Allows air transmission, but HIV doesn't spread via respiratory droplets.
• B: Allows air and saliva, both incorrect as HIV requires direct fluid exchange.
• C: Includes saliva but excludes semen, ignoring sexual transmission route.

Final answer: D