I know you did not mean to cause offense, but "retarded question" is offensive. People with mental disabilities deserve better than being called "retards" or "retarded" and deserve better than people referring to what they perceive as silly or dumb as "retarded."
Please drop this word from your English vocabulary.
Should we also drop the word "stupid" and what about "idiot"? Because these terms are also sometimes used to refer to people with mental disabilities.
In general the term "retarded" is rejected as a correct term to refer to mentally challenged people. There could be discussion about the nature of this term nowadays, because in most cases it is
not used to refer to the mentally ill, but indeed to something or someone that is considered as extremely stupid or idiotic(without the object/person in question actually being mentally handicapped).
Perhaps we might need to consider that the term has evolved to having a different meaning than it used to. Especially when it comes to the general public, and we might need to stop relating it to the mentally ill. Because that way we keep acknowledging that "retard" is synonymous with "person that is mentally ill" while that was an undesirable way of referring to them in the first place.
While one would do good in dropping the term from their vocabulary we can not expect every english speaker(especially on the Internet) to be civilised and literate enough for that.
This is all horribly off-topic but I feel like it had to be said.