Auditor rotation rules require: A. Engagement partners to rotate off a private audit client after 5 years. B. All partners to rotate off a public audit client after 5 years with a cooling off period of two years. C. Audit engagement and EQC review partners of issuer clients are required to have 5 year "cooling off" periods when servicing public clients for 5 years. D. Lead partners' service time prior to an IPO is not included in determining the number of years they can serve on the issuer client after the SEC registration