文档介绍：:..?(a)';'(b)'<='(c)"'"(d)"a"Correctanswer:?(a)$(b)if(c)_(?(a)';'(b)'<='(c)"'"(d)"a"Correctanswer:?(a)$(b)if(c)_(theunderscore)(d)0Correctansweris(d),garbagecollectionrefersto(a)automaticbalancingofparenthesisperformedbysomeeditors(b)removalofJavaprogramsthatcouldcausedamagetoasystem(c)ments(d)automaticreturnofme