Means shall be provided for automatically giving audible warning of the release of fire-extinguishing medium into any ro-ro spaces and other spaces in which personnel normally work or to which they have access. The pre-discharge alarm shall be automatically activateD. The alarm shall operate for the length of time needed to evacuate the space, but in no case less than ( ) seconds before the medium is releaseD
A.5 B.10 C.15 D.50正确答案D