Im sorry but this is a statement not a question
The best answer would be Letter B - to entertain.
The author merely would like to provide amusement to the readers at his expense. It certainly does not persuade, explain, nor inform anything since it states - <span>But why bother with the descriptions; you’ve probably already grasped the idea!</span> - which could be taken as a witticism.
Love is the answer you are looking for. Orsino is in love with Olivia. Olivia is in love with Cesario. Viola is in love with Orsino. Therefore your answer is Love.
I’m pretty sure Lyddie had been reading Oliver Twist earlier on in the novel.