an accountant is hired to give expert witness services on behalft of a group of companies. One of those companies is a client for whom the accountant performs a feview engagement. that client is not desingnated as a "lead plaintiff" or "defendent" of the group, nor does the client have sole decision making power to select or approve the expert witness. Which of the following is correct: a independence is impaired in all instances b independence is impaired if the client constitutes $10$ percent of the members of the group, including the claim c independence is ipaired if the client constitutes $20$ percent or more of the member of the group, including the claim d independence is impaired if the client constitutes $15$ percent of the members of the group, including the claim