[单选题]
Which component of blood is mainly compos/slhr h+hqs58zkn- b6ed of water and6tgjc rc9c;/ e8zi+m v transports water-solubl9 6mze+rc;c8 cvj /igte substances to different parts of the body?
A. Red blood cells
B. White blood cells
C. Platelets
D. Blood plasma