The phrase "a reasonable question to" is correct and usable in written English.
You can use it when introducing a question that is logical or justifiable in a given context.
Example: "Given the circumstances, it is a reasonable question to ask why the project was delayed."
Alternatives: "a valid inquiry to" or "a sensible question to".
A reasonable question to consider is whether staffing is the reason why TCA statistics differ between the US and European models?
I think it's a reasonable question to put on the table, but I see no reason to consider it at this time".
"WHERE'S the beef?" is always a reasonable question to ask.
Just how far local newspapers can be cut back is a reasonable question to ask, though.
The question might seem rhetorical to the jaded or cynical, but it is still a reasonable question to ask.
Actually, it was more like, "Are you kidding!!" Well, it seemed like a reasonable question to ask him.
Here is a perfectly reasonable question to ask of a special issue devoted to fiction: Why has it got so much in it about food?
If there is one thing I hear from every parent or applicant I speak with from now until December it's this: "How do you even start to write the Common Application Essay?" It's a perfectly reasonable question to ask when staring at a blank computer screen trying to come up with a story which will help that applicant get admitted to the school of their choice.
A perfectly reasonable question to ask of people like me, who define "religion" in a way that plays down theology, is why something like football should not be a religion.
This is a very reasonable question to ask.
One of six jurors, there is a reasonable question as to how the prosecution passed on B37 to allow her to be seated when most professional jury selection consultants would have quickly raised red flags, not just regarding her enigmatic responses but also displaying a less than open and inquiring mind.
