单项选择题
A.the final judge of the reliance the mariner can place on the information given
B.its immediate importance cannot always be verified before promulgation
C.through imperfections in the survey on which it is based，or subsequent alterations to the topography or sea floor
D.deferring the promulgation of certain less important information
单项选择题 Charts showing the coast of Mexico are produced by the United States（）.
单项选择题 A chart with a scale of 1:80，000 would fall into the category of a（）.
单项选择题 A chart projection depicting the poles and a small area on either side of a connecting meridian，that is sometimes used for star charts，is the（）.