Though 'due to' can be used to explain a reason, it is not a conjunction but a preposition (that means you can not join a clause with it, while it can only join a noun), no matter it is used formally or orally.
We may say: I can not give out my opinions to them, due to the deficiency of suitable answers in my mind.
I think opinion and response are similiar, so it appears redundant. Sometimes a longer sentence might not be better than a shorter one.
Besides, if you wanna use 'due to', be aware of the comma (,), for it can not be omitted.
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3,what job
do you prefer in your work?
Your boss, certainly.
