The correct answer is A. Say that he will answer after consultation.
A teacher should always be willing to answer questions from their pupils. If a teacher is not able to answer a question, they should say that they will answer after consultation. This shows that the teacher is taking the question seriously and is committed to finding an answer. It also shows that the teacher is not afraid to admit when they do not know something.
Option B is incorrect because it is not appropriate for a teacher to rebuke a pupil for asking a question. Pupils should feel comfortable asking questions, and teachers should be supportive and encouraging.
Option C is incorrect because it is not appropriate for a teacher to say that a question is wrong. Pupils should feel comfortable asking questions, even if they are not sure if they are right or wrong. Teachers should be patient and understanding when answering questions.
Option D is incorrect because it is not appropriate for a teacher to feel shy of their ignorance. Teachers are not expected to know everything, and it is perfectly acceptable to say that you do not know the answer to a question. It is important to be honest with pupils and to be willing to learn new things.