【正确答案】 A

【答案解析】[理由] 本句测试3个表“可能的”形容词(likely、possible、probable)的用法：
1) likely用于下列固定结构：
It is likely that+S+V ……很可能……
=sb/sth is likely to V
[例] It is likely that John will do it.
=John is likely to do it
(约翰很有可能会做这件事。)
2) possible用于下列结构：
It is possible that+S+V ……可能……
=It is possible for sb/sth to V
[例] It is possible that John will do it.
=It is possible for John to do it.
(约翰可能会做这件事。)
3) probable用于下列结构中：
It is probable that+S+V ……很可能……
[例] It is probable that John will do it.
(约翰很可能会做这件事。)
空格前有主语a company，之后有动词is，且空格也有不定式短语to close down，故得知仅(A)为正选。
若空格内要置入probable或possible时，原句的主语均应使用形式主语it，改正如下：
As a result of poor management, it is possible/probable that Sableline, a company once famous the world over for its quality toys, will close down in two years.
(D)的maybe(也许)为副词，使用时恒置于句首。
[例] Maybe he will come this afternoon.
(他今天下午也许会来。)
若欲使用(D)，原句应改正如下：
As a result of poor management, maybe Sableline, a company once famous the world over for its quality toys, will close down in two years.