What is a difference between DMVPN and sVTI?

What is a difference between DMVPN and sVTI?
A . DMVPN supports tunnel encryption, whereas sVTI does not.
B . DMVPN supports dynamic tunnel establishment, whereas sVTI does not.
C . DMVPN supports static tunnel establishment, whereas sVTI does not.
D . DMVPN provides interoperability with other vendors, whereas sVTI does not.

Answer: B