You are carrying cargoes of crotonaldehyde,phosphoric acid,and morpholine on your multiple-product tanker. Which of the following statements is TRUE? ()
A. Each of the cargoes must be segregated from the other by at least two barriers
B. The minimum protective clothing required for taking samples of phosphoric acid is goggles or a face shield
C. Aluminum,copper,and zinc are prohibited in all valve parts in contact with these cargoes
D. The required warning sign must have the legend "cancer hazard" added to it