Why is the carnitine shuttle considered an antiport mechanism?

• A. It transports both carnitine and fatty acyl CoA out of the mitochondrial matrix.
• B. It transports fatty acyl CoA out while bringing carnitine into the mitochondrial matrix.
• C. It transports both carnitine and fatty acyl CoA into the mitochondrial matrix.
• D. It transports carnitine out while bringing fatty acyl CoA into the mitochondrial matrix.

Answer: (D)