which will assign the user_r role and the user_t domain to their login session?

When a user logs into a system using SSH, what is the format of SELinux security context which will assign the user_r role and the user_t domain to their login session?

A.
user_r:user_t system_r:sshd_t

B.
sshd_t:system_r user_t:user_r

C.
system_r:sshd_t user_r:user_t

D.
user_t:user_r sshd_t:system_r