General Knowledge quiz
You should generally avoid redundancy when programming.

I'd make a list and loop through it

QUESTIONS = [("A vehicle with the national registration code ‘PK’ would originate from which country?", "Pakistan"),
             ("In which English county is Blenheim Palace?", "Oxfordshire")] # Add more to this list

for n,(question, answer) in enumerate(QUESTIONS, 1):
    time.sleep(2)
    print("Question", n)
    time.sleep(2)
    user_answer = input(question)
    if user_answer.lower() == answer.lower():
        print("Correct answer")
        score += 1
    else:
        print("Incorrect answer, the correct answer is", answer)


And so on

Hope this helps :-)