Answer:
A. learning history encourages a more multicultural viewpoint on the world
Step-by-step explanation:
The best example of a topic that is too broad is learning history encourages a more multicultural viewpoint on the world because history is subject in which you will have to cover a large and extensive range of topics to learn it.
The other options the history of the English monarchy, the importance of teaching history in schools and the positive effects of teaching history to students at a young age are not topics as extensive to cover.