Which of the following statements are true of capillaries? (Read carefully and select all of the correct statements.)

A)Their walls are made of simple squamous epithelium.
B)Blood plasma in capillaries becomes tissue fluid by the process of filtration.
C)The process of osmosis returns some tissue fluid to the blood at the venous end of capillaries.
D)The process of filtration brings dissolved nutrients to tissues.
E)The colloid osmotic pressure of blood is created by plasma proteins such as albumin.
F)The flow of blood into a capillary network is regulated by a precapillary sphincter.