What command will open a connection with a remote POP3S (POP3 over SSL) server?

The OpenSSL command can be used to test connections with various secure services. What command will open a connection with a remote POP3S (POP3 over SSL) server?

A.
openssl connect host pop.example.com:pop3s

B.
openssl connect pop.example:pop3s

C.
openssl s_client connect pop.example.com:pop3s

D.
openssl s_client pop.example.com:pop3s