Hello. You did not submit the text to which this question refers, which makes it impossible for this question to be answered. However, I will try to help you as best I can.
The concept of "ignorance" refers to lack of knowledge. This means that an ignorant person is one who is acting naively or incorrectly, because he does not have enough knowledge to perform a certain action. In that case, to answer the above question, you must read the text to which the question refers and identify how the concept of ignorance fits into Oberon's attitude of putting flower juices in the "eyes of the Athenian man."