Which two actions are recommended when adding a host to a vSAN cluster? (Choose two.)

An organization is facing vSAN storage capacity challenges on one of their vSAN enabled clusters, while other vSAN enabled clusters are underutilized. The current vSAN version is 7.0 U1.
Which vSAN feature should be used to resolve this challenge in the quickest way?

An Application Clustering Solution requires an in-guest attachable LUN which can be shared across two different VMs.
Which vSAN feature can meet this requirement?

Which two conditions should be verified before removing an ESXi host from a vSAN cluster? (Choose two.)

Skyline Health vSAN HCL DB up-to-date health check is alerting in red in a newly deployed vCenter Server.
Which two options are the possible solutions for this problem? (Choose two.)