I suffer from no ....... about my capabilities.

illusion means false belief.so it is the correct ans

Review it please

Illusion: something that seems to exist but in fact does not, or seems to be something that it is not. Examples:
1. Mirrors in a room often give an illusion of space.
2. The idea of absolute personal freedom is an illusion.

Doubts: a feeling of being uncertain about something or not believing something.

Examples:
1. New evidence has cast doubt on the guilt of the man jailed for the crime.
2. She knew without a shadow of a doubt that he was lying to her.
3. Whether he will continue to be successful in future is open to doubt.

what is difference between illusion and doubt