When was District Dir of KPK merged in Pakistan?

When was District Dir of KPK merged in Pakistan?A. 1949
B. 1956
C. 1969
D. 1973

At the time of independence, Dir was a princely state ruled by Nawab Shah Jehan Khan. It was merged in Pakistan in 1969 and later on declared a district in 1970. The district was formed in 1996, when the district of Dir was divided into Upper Dir and Lower Dir. The District borders with Swat District on its East, Afghanistan on its West, Upper Dir and Chitral on its North & north-west respectively and Malakand and Bajaur Agency on its South.Major Castes in district are Yusafzis,Qazi (Siddiques), Utmankhel & Shinwari.