B 分析:根據(jù)假分?jǐn)?shù)和真分?jǐn)?shù)的意義可知:要使是假分?jǐn)?shù),則X≥9,是真分?jǐn)?shù)X<10,據(jù)此分析解答. 解答:要使是假分?jǐn)?shù),則X≥9,是真分?jǐn)?shù)X<10,即9≤X<10,就是X=9; 故選:B. 點評:本題主要考查真假分?jǐn)?shù)的意義,注意分子大于等于分母的分?jǐn)?shù)是假分?jǐn)?shù),分子小于分母的分?jǐn)?shù)是真分?jǐn)?shù).