Correct option is A
The option that contains a grammatical error is option (a) that King Lear confided to.
• The sentence is about King Lear and his daughter Cordelia.
• However, the word 'confided' is not appropriate in the context of the sentence, as it means to share a secret or private matter with someone.
• In the given sentence, it is more appropriate to use the word 'conferred', which means to grant or bestow (something) on someone.