Lady Catherine is at her absolute worst in this scene. "Elizabeth had mentioned her name [Lady C's] to her mother, on her ladyship's entrance, though no request of introduction had been made". This shows how the rules of etiquette could ironically be used to display rudeness instead of good manners by someone of "superiority". Since Lady Catherine has precedence over the Bennets and chooses not to be introduced to Mrs. Bennet and Kitty, they are not allowed to speak to her in their own home. Lady C says to Lizzy something along the lines of 'That woman, I suppose is your mother.' Mrs. Bennet, it seems, took this as a form of recognition of sorts and thus, when Lady C then asks Lizzy if that one is her sister, Mrs. Bennet answers the question, anxious to be able to speak to Lady C. Mrs. Bennet is bound to have her share of the conversation, etiquette or not. LOL.