In aerospace, what does it mean when a symbol or indication is assigned, signifying that the aerospace vehicle, equipment, or SE is considered unsafe or unserviceable and will not be flown or used until the unsatisfactory condition is corrected and/or the symbol is cleared?
A) The symbol is a routine indicator and can be ignored.
B) Continue using the vehicle or equipment with caution.
C) The condition is acceptable for a limited period.
D) The aerospace vehicle or equipment is grounded until the issue is resolved.