Mark, an audit manager working on the attestation engagement for Seaberry Enterprises has just learned from the client's Chief Financial Officer that the firm recently completed a major update and upgrade of their purchasing system. As a result of this information, what might Mark decide to do as part of the audit of this area? 

Mark may decide to issue a qualified opinion on the audit of the client's purchasing process, as the recent upgrade has increased inherent risk.

Mark may decide to obtain written assurances from senior management to gain extra assurance in this area. 

Mark may decide to evaluate segregation of duties in this area, to determine how access to the purchasing system is controlled.

None of these