单项选择题
A.Nitric acid
B.Amides
C.Alcohols，glycols
D.Phenols，cresols
单项选择题 According to the Chemical Data Guide，1，3 - pentadiene possesses which characteristic? （）
单项选择题 According to regulations，access to a cargo pumproom in a tank vessel carrying grades C or D liquid cargo shall be（）.
单项选择题 Access to a cargo pumproom on a tank vessel carrying grades A，B，C or D liquid cargoes shall be（）.