求教XDF小兰一题

mirandatsui

p128 335
The presidents of a consulting firm analyzed the decisions made about marketing by her clients and concluded that the decisions were correct only about half of the time. The conclusion above depends on the presupposition that__
D marketing decisions are just as likely to be correct as they are to be incorrect
E it is possible to classify a marketing decision properly as being either right or wrong

结论是decisions were correct only about half of the time 我想请问下这句话怎么理解。因为我理解为"决定不是时时正确"但是显然不符合答案。求解答。

（答案为E）

顺便再问下，我从官网下载的PREP只有两套机考。PREP还有其他题目么？

非常感谢~