In this task, you are given a question. You have to answer the question based on your information.
One example: Roman Yakub won first price in a Choral Composition Competition at a liberal arts college founded by who?
Solution is here: William Egbert
Explanation: This is a good example, and output correctly answers the question.

Now, solve this: Which four kingdoms did the Great Heathen Army invade?
Solution:
Northumbria, Mercia, East Anglia and Wessex