In which key vaults can you store the encryption key for VM1?

You have an Azure subscription named Sub1 that contains the Azure key vaults shown in the following table.

In Sub1, you create a virtual machine that has the following configurations:

• Name:VM1

• Size: DS2v2

• Resource group: RG1

• Region: West Europe

• Operating system: Windows Server 2016

You plan to enable Azure Disk Encryption on VM1.

In which key vaults can you store the encryption key for VM1?
A . Vault1 or Vault3 only
B . Vault1, Vault2, Vault3, or Vault4
C . Vault1 only
D . Vault1 or Vault2 only

Answer: A

Explanation:

"Your key vault and VMs must be in the same subscription. Also, to ensure that encryption secrets don’t cross regional boundaries, Azure Disk Encryption requires the Key Vault and the VMs to be co-located in the same region." https://docs.microsoft.com/en-us/azure/virtual-machines/windows/disk-encryption-key-vault