Question: To enhance email security, a company implements DKIM. What aspect of email security does DKIM primarily address?

1. Key Length
2. Key Exchange
3. Symmetric
4. Asymmetric

Correct answer is Key Length. Why?

When you say strong encryption algorithm, that implies the key length is already strong therefore it's deemed to be "strong encryption" in the first place. RSA 2048/4096, aes-256-gcm are some of the examples of "strong encryption" alogrithms. But if you use a weak key exchange algorithm like plain diffie hellman, then it could be problematic no??