Rosalita's, coming from a tight culture background, thought the comment regarding her friend was sexist and offensive. Role identities is a set of behavioral expectations associated with a particular position in a group. Since Ronald's had an influential decision on a new candidate to hire for the company, Rosalita's expectations of Ronald's role was that of professionalism, serious, courteous, etc. Thus, the misunderstanding arose when Ronald didn't live up to Rosalita's role expectation of him. Prejudice in a form of sexism.
Sexism occurs when one assign characteristics to other based on their sex.
Thus, the misunderstanding arose because Rosalita's knew that her friend wasn't that kind of a person and took offense at Ronald's remark. Last, but not least, the environmental factor. Ronald, having been told a little bit about Rosalita's friend by Rosalita herself regarding the circumstances why her friend was interested in seeking employment with the company. Although Ronald's knew of Rosalita's friend circumstances, he disregarded it and in a way criticized and made fun of the situation. Thus, Rosalita's thought that her friend did not deserved the criticism and was upset at Ronald.