Answer: The United States, the United Kingdom, China, Russia and France
Step-by-step explanation:
The United States of America (1945-Present)
The United Kingdom of Great Britain and Ireland (1945-Present)
The People's Republic of China (1971-Present)*
The Fifth French Republic (1958-Present)**
The Russian Federation (1991-Present)***
*Prior to 1971, the China was represented as the ROC from 1945-1948 when they were still on the mainland. After the loss of the Civil War, the ROC represented China via Taiwan and held that from 1949-1971 when the UN gave that seat to the People's Republic of China.
** When the UN Charter was signed, France was in a provisional period of government as it was just liberated from the grasps of Nazi Germany. The Fourth Republic took that seat until 1958 because the French government were losing control of their colonies culminating into the Algerian Crisis of 1958. Afterwards, the Fourth Amendment was dissolved and the French people, in a referendum allowed the establisment of the Fifth Republic,
*** When originally signed, the USSR held the seat from 1945-1991. In 1991 massive political upheaval destroyed the USSR and it became the Russian Federation