The boy talked his mother _____ buying him a new homecomputer.[ ]

A. of  

B. over

C. to  

D. into

全淹没气体灭火系统是指在规定时间内，向防护区喷放设计规定用量的气体灭火剂，并使其均匀地充满整个防护区的灭火系统。