According to a recent study conducted at over 100 American universities, the number of college graduates interested in pursuing a career in financial services is likely to double by 2010.
a) is likely to double
b) are likely to increase by twice
c) are likely to double
d) will double
e) will increase by twice
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The OA is A, not D.
How do I know that D is incorrect? Shall I treat the word 'likely' as a correct constant and focus only on a correct form/meaning of the verb 'is'?