During Placement of Sealant

During placement of sealant:

A) if an etched tooth becomes contaminated with saliva, the etching and rinsing steps need not be repeated.
B) the self-cured sealant is cured with a light source for at least 20 seconds.
C) moisture enhances retention of the sealant by the fissure.
D) a small cotton pellet may be used to remove sealant that has failed to polymerize because of exposure to air.
E) if a fluoride treatment is used in conjunction with the pit and fissure sealant, the fluoride treatment is applied before the sealant has polymerized.