When Considering Using a Vendor to Help Support Your Security

When considering using a vendor to help support your security devices remotely, what is the BEST choice for allowing access?

A) Vendors uses their own laptop and logins with same admin credentials your security team uses
B) Vendor uses a company supplied laptop and logins using two factor authentication with same admin credentials your security team uses
C) Vendor uses a company supplied laptop and logins using two factor authentication with their own unique credentials
D) Vendor uses their own laptop and logins using two factor authentication with their own unique credentials