The answer is: none of the above.
To clarify, the phrase ‘all real numbers x’ means that the set of solutions includes every possible real number without any restrictions. The typical notation for this is R, representing the set of all real numbers.
In many mathematical contexts, when you are presented with specific conditions or constraints that limit the values of x (for example, x > 1, x < 1, or x = 1), none of these sets would encompass all real numbers since they impose some form of limitation.
Thus, if your options include specific constraints or isolated points, then the correct response to the question is indeed ‘none of the above’, because none of those options can represent the entirety of the real number set.