What is the most important item the SE must have in place with the prospect before moving forward with a POC?

During a sales motion with a new prospect, the prospect asks to do a POC so they can experience Nutanix in their environment.

What is the most important item the SE must have in place with the prospect before moving forward with a POC?
A . Start date of the POC
B . Defined and measurable success criteria
C . Meeting frequency
D . Number of Nodes/Block to be used during the POC

Answer: B