Given the following URL https://courses.company.com/ccna, which part is the hostname?

(A) https
(B) courses
(C) courses.company.com
(D) company.com
(E) company.com/ccna

courses.company.com is the correct answer.

The hostname is the text between the // and the first period. Although not required to be the hostname, it's a practice done by many companies.