You have an Active Directory domain that syncs to an Azure Active Directory (Azure AD) tenant. The on-premises network contains a VPN server that authenticates to the on-premises Active Directory domain. The VPN server does NOT support Azure Multi- Factor Authentication (MFA). You need to recommend a solution to provide Azure MFA for VPN connections. What should you include in the recommendation? 

Answer options:

A. Azure AD Application Proxy
B. an Azure AD Password Protection proxy
C. Network Policy Server (NPS)
D. a pass-through authentication proxy

C

Reference: https://docs.microsoft.com/en-us/azure/active-directory/authentication/howto-mfa-nps-extension-vpn