Which of the following are credentials supported by VPN-1/FireWall-1 for a gateway-to-gateway encryption?

In gateway-to-gateway encryption, gateways identify themselves by presenting their credentials.
Which of the following are credentials supported by VPN-1/FireWall-1 for a gateway-to-gateway
encryption? (Choose two)

A.
Certificates

B.
Cookies

C.
Tokens

D.
Pre-shared secret

E.
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