Which secure mail should you choose?

Question

Information Security

What do you think is the most secure mail?

Answer 1

The best security system is anonymity.

Answer 2

Maybe protonmail.com

Answer 3

Any where there is a 2-factor authentication.

Answer 4

Who is the alleged perpetrator? Neighbor Vasya? Employer? Jean? State?
Different people have different abilities. "Safe mail" usually means keeping secret the following:
- the fact of the relationship between citizen Ivanov and the [email protected] mailbox
- the address book
- the text of the letters
- the send log (it is available indirectly by dates in the sent folder)
Different people have different possibilities for topics or otherwise gain access to it all.