David Hilbert described this mathematical concept in a thought experiment about the Grand Hotel, in which he explained that a completely occupied hotel could still hold this many guests. Georg Cantor explained this mathematical concept, of which cardinal numbers of this are symbolized with the aleph symbol. According to Cantor, the set of integers is countably this type of number, while this type of set of real numbers is uncountable. For 10 points each, name this mathematical concept that describes a type of number that is larger than any natural number.
A) Irrational numbers
B) Imaginary numbers
C) Complex numbers
D) Transfinite numbers