?under section $600$ ?for IFAC and IESBA guidance, which of the following is a possible safeguard when a member of the engagement team has provided safekeeping services and tax calculations for an audit client Under Section $600$ ?for IFAC and IESBA guidance, which of the following is a possible safeguard when a member of the engagement team has provided bookkeeping services and tax calculations for an audit client?

a$.$ ?The engagement team member should be rotated off the engagement team.

b$.$ ?The engagement team member should be placed in a supervisory position and not work with any of the actual review.

c$.$ ?Safeguards are not available to reduce this independence threat to an acceptable level.

d$.$ ?The firm should document the relationship in its opinion letter.