The proof shows that the set `K = {a + b * 2^{1"/"3} + c * 2^{2"/"3} :`
`a , b , c in QQ }` is exactly the field extension `QQ(2^{1"/" 3})`, based on a theorem stating the form of elements in such extensions. What is the most significant consequence of this formal connection for proving that K is a subfield of `RR`:
A) It allows to calculate the exact numerical values of any element in K, which is necessary to show they are real numbers.
B) It removes the need for a tedious, element-by-element verification of all field axioms (like closure under multiplication or existence of inverses) for the set K ?