Why are certificates preferred over pre-shared keys in an IPsec VPN?

A.
Weak scalability: PSKs need to be set on each and every Gateway

B.
Weak performance: PSK takes more time to encrypt than Drffie-Hellman

C.
Weak security: PSKs can only have 112 bit length.

D.
Weak Security: PSK are static and can be brute-forced.