Answer:
The correct answer is A. The United Kingdom and Nigeria both rely on popular elections as a source of legitimacy.
Step-by-step explanation:
Both the United Kingdom and Nigeria are democratic nations that, with their differences in political organization, establish the legitimacy of their respective governments through the popular will embodied in elections.
Thus, Nigeria is a presidential federal republic, where its president Muhammadu Buhari was elected in 2015 for a period of 4 years of government, and re-elected in 2019 for another 4 years.
In turn, the United Kingdom is a parliamentary monarchy, where the Head of State is Queen Elizabeth II, while the Head of Government and main political representative of the nation is Boris Johnson, who was appointed by the British Parliament in 2019. In turn, the composition of Parliament is determined through elections by the British people themselves.