Which Secretary-General is known for his posthumous Nobel Peace Prize due to his efforts in the Congo crisis?

Dag Hammarskjöld

The correct answer is Option 2-  Dag Hammarskjöld

Dag Hammarskjöld (1953-1961) Sweden; Economist and lawyer; worked for resolving the Suez Canal dispute and the decolonisation of Africa; awarded Nobel Peace Prize posthumously in 1961 for his efforts to settle the Congo crisis; the Soviet Union and France criticised his role in Africa.