The correct answer is: A. April, 1947
United Nations Security Council Resolution 47 was adopted on April 21, 1947. It called for the establishment of a United Nations Truce Supervision Organization (UNTSO) to supervise the implementation of the Armistice Agreement between Israel and the Arab states.
UNTSO was the first peacekeeping operation established by the United Nations. It has been in operation ever since, and is currently deployed in the Golan Heights, the Sinai Peninsula, and the Lebanon.
The other options are incorrect because they are not the years in which United Nations Security Council Resolution 47 was adopted.