Please Help! Which of the following is one of the changes implemented by Mustafa Kemal, Turkey's first president

He established a communist form of government, aligning the country with the Soviet Union.
B.
He created a new national religion, uniting the different cultural groups within the country.
C.
He ended Turkey's relations with Europe, causing the country to become quite isolated.
D.
He made Turkey into a secular state, ending the Muslim influence on politics.