When two subjects are joined by as well as, the verb agrees in number and person with the first one. So, ‘was’ should be changed to ‘were’.
What is the currency of Japan?
What is the capital of Madagascar?
Which of the following is the currency of Armenia?
What is the capital of Australia?
Which of the following is the capital of Mauritius?
Where is the capital of Switzerland?
What is the currency of Yemen?
What is the currency of Japan?
Which city was the capital of Pandya dynasty?
Seoul is the capital of which country?