Who is the present Secretary-General of the United Nations?

António Guterres

The correct answer is Option 4 - António Guterres

António Manuel de Oliveira Guterres is the present Secretary General of the UN since 2017. He was the former Prime Minister of Portugal from 1995 to 2002 and was also the United Nations High Commissioner for Refugees from 2005–2015. He also held the position of the President of the Socialist International from 1999 to 2005. He is serving as the ninth secretary–general of the United Nations.

Ban Ki-moon of the Republic of Korea was the Secretary General of the UN before Antonio Guterres, i.e., from 2007-2016. He was the second Asian to hold the post.
Kofi Annan of Ghana was the Secretary General of the UN before Ban-Ki Moon. He declared the US-led invasion of Iraq an illegal act.
U Thant of Burma was the third Secretary General of the UN. He worked to resolve the Cuban Missile Crisis and end the Congo crisis.