Idioms and Phrases - Verbal and Reasoning

In the following questions four alternatives are given for the idiom/phraseitalicised and underlinedin the sentence. Choose the alternative which best expresses the meaning of idiom/phrase.
Q1:

Sanjay is very different about passing the Civil Services Examination this year.

A Dead sure of

B Very hopeful of

C Lacking self confidence about

D Reasonably certain of

ANS:C - Lacking self confidence about

No answer description is available.