In SAP Ariba guided buying, which activities does a specialized item from enable requesters to perform?

In SAP Ariba guided buying, which activities does a specialized item from enable requesters to perform?
A . Initiate a sourcing request to centralized procurement
B . Order products that are NOT in the company catalog
C . Provide additional information to specify the product they want
D . Conduct three bids and a buy for highly technical items

Answer: D