Draft readings shall be considered as（）in the draft survey report．

A.Filter masks with a combination filter should be brought and used whenever necessary
B.Only explosion-proof equipment（marked EEx）should be used
C.Avoid breathing petroleum gases，especially if they come from sour crude（smell of rotten eggs）
D.so far as possible，take early and substantial action to keep well clear

A.to／for
B.for／to
C.by／through
D.through／for

A.only when the cargo is within its rail
B.during the time when loading or unloading is going on
C.after the cargo is checked by tallymen
D.as soon as loading or discharging begins