Answer:
It must be a tricky question that is hard to answer.
It cannot be a question that is based on a simple fact.
Step-by-step explanation:
The characteristics of an effective research question for an informative essay are the question must be a tricky question that is hard to answer and cannot be a question that is based on a simple fact.
This is so because a tricky question that is hard to answer goes beyond common knowledge and inspires curiosity. The interesting tricky question helps professional researchers to research more and come with some more relevant facts.
The question should not be based on simple fact because it can restrict the opportunity of research on a particular topic and it will not contribute to the existing body of research.
Hence, the correct answer is:
"It must be a tricky question that is hard to answer.
It cannot be a question that is based on a simple fact."