Choose this if your SaaS product is an add-on to a Microsoft product. This agreement is signed by both parties (if you require terms and conditions, that are accepted by the customer, not signed, choose the SaaS Add-on End User terms).
Clarify the extent of your responsibility, failures could be due to the Microsoft product or Microsoft hosting.
Given that the SaaS is an add-on to a Microsoft service, you provide no uptime commitment or service credits. Support services are reasonable endeavours only, with no service levels.