One way Mustafa Kemal created a modern, secular, nationalist, Turkish state in what used to be the Ottoman Empire was by _____.

A. switching the Arabic alphabet to the Roman one and the Islamic calendar to the one used in Europe
B. encouraging people to dress in traditional Ottoman attire
C. bringing in U.S. advisors to aid in the process
D. gradually and slyly introducing European ideas and labeling them as Turkish national traditions