18. Lark Manufacturing Company initiated a voluntary Quality
Circles program for machine operators. Independent surveys of
employee attitudes indicated that the machine operators
participating in the program were less satisfied with their work
situations after two years of the program’s existence than they
were at the program’s start. Obviously, any workers who
participate in a Quality Circles program will, as a result, become
less satisfied with their jobs.
Each of the following, if true, would weaken the conclusion drawn
above EXCEPT:
(A) The second survey occurred during a period of recession when
rumors of cutbacks and layoffs at Lark Manufacturing were
plentiful.
(B) The surveys also showed that those Lark machine operators who
neither participated in Quality Circles nor knew anyone who did so
reported the same degree of lessened satisfaction with their work
situations as did the Lark machine operators who participated in
Quality Circles.
(C) While participating in Quality Circles at Lark Manufacturing,
machine operators exhibited two of the primary indicators of
improved job satisfaction: increased productivity and decreased
absenteeism.
(D) Several workers at Lark Manufacturing who had participated in
Quality Circles while employed at other companies reported that,
while participating in Quality Circles in their previous companies,
their work satisfaction had increased.（E）
(E) The machine operators who participated in Quality Circles
reported that, when the program started, they felt that
participation might improve their work situations.
不明白应该用什么思路？
这类except题很难，有什么好的解题方法？ | 
