Despite recent increases in sales and cash flow that have propelled automobile companies' common stocks to new highs, several industry analysts expect automakers, in order to conserve cash, to set dividends more conservatively than they were.

(A) to set dividends more conservatively than they were
WRONG they were does not completes the meaning of the sentence

(B) to set dividends more conservatively than they have been
WRONG the sentence is ending with they have been sounds a little awkward and does not coney the meaning properly

(C) to be more conservative than they have been in setting dividends
CORRECT no error and completes the meaning

(D) that they will be more conservative than they were in setting dividends
WRONG pronoun ambiguity- is hard to understand whether they here is referring to the analysts or the automakers
Idiomatic error- expect that is wrong

(E) that they will be more conservative than they have been to set dividends
WRONG pronoun ambiguity and idiomatic error- same as D