What is the Service Level Agreement (SLA) for Email Security.cloud Service Availability?

What is the Service Level Agreement (SLA) for Email Security.cloud Service Availability?

A. 95%
B. 99.999%

C. 100%

D. 99%

Reference: https://www.pugh.co.uk/wp-content/uploads/2017/08/Symantec-Email-Security.cloud_.pdf