Candid is to indirect as honest is to

Candid and indirect refer to opposing traits. Honest and untruthful refer to opposing traits.
The answer is not choice a) because, Frank means the same thing as candid.
Wicked (choice b) is incorrect because, even though it refers to a negative trait, it does not mean the opposite of honest.
Choice c) is incorrect because Truthful and Honest mean the same thing.