Answer:
"International quizzes currently take place in the Western Cape and KwaZulu-Natal, aren't they?"
Step-by-step explanation:
Question tags are question words added at the end of a sentence to make it into an interrogative sentence. Such question tags may include "is/isn't it?, Do/don't they" etc. depending on the sentence.
The given sentence "international quizzes currently take place in the Western Cape and KwaZulu-Natal" is positive. So, first thing is to make the question tag in the negative form. And the subject is plural. Moreover, the tense of the verb "take" is in the present tense. Therefore, the question tag will also be in the present tense, for question tags should be the same tense as the sentence.
Thus, the final sentence with a question tag will be
"International quizzes currently take place in the Western Cape and KwaZulu-Natal, aren't they?"