Which caliph of the Muslims ordered the collection of Ahadith of the official level:...? Mcqs

Which caliph of the Muslims ordered the collection of Ahadith of the official level:...?

(A) Hazrat Usman RA

(B) Hazrat Umar RA

(C) Harat Umar Bin Abdul Aziz RA

(D) Hazrat Ali RA