The more effective research question given from the options on the Voyager missions is D. What were the most important discoveries of the Voyager probes?
A research question should not be too specific such that it would have a basic and short answer like options A and B.
It should also not be so broad that too much information will be needed like in option C. Option D is best because it is not too specific, and not top broad either.
Find out more on formulating research questions at https://brainly.com/question/10129052.
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