Which statement is supported by the data?

Which statement is supported by the data?

• A. HIV infection destroys immune cells, weakening the immune system.
• B. HBV is transmitted through air.
• C. HBV vaccine licensing occurred in 1990.
• D. HBV cannot survive outside the body.

Answer: (A)

HIV targets and damages the very cells that coordinate the immune response. It primarily infects CD4+ T lymphocytes, and as these cells are destroyed or impaired, the immune system loses its ability to mount effective defenses. This leads to a weakened immune system and greater vulnerability to infections and illnesses, which is exactly what the data show for HIV infection: a progressive decline in immune function due to the loss of these crucial immune cells. The other statements don’t fit the data about HBV. HBV is transmitted through blood and bodily fluids, not through the air. The vaccine licensing occurred earlier in the 1980s, not in 1990. And HBV can survive outside the body for days, so it is not correct to say it cannot survive outside the body.

HIV targets and damages the very cells that coordinate the immune response. It primarily infects CD4+ T lymphocytes, and as these cells are destroyed or impaired, the immune system loses its ability to mount effective defenses. This leads to a weakened immune system and greater vulnerability to infections and illnesses, which is exactly what the data show for HIV infection: a progressive decline in immune function due to the loss of these crucial immune cells.

The other statements don’t fit the data about HBV. HBV is transmitted through blood and bodily fluids, not through the air. The vaccine licensing occurred earlier in the 1980s, not in 1990. And HBV can survive outside the body for days, so it is not correct to say it cannot survive outside the body.