Finite Language Closure Properties Let L={F| F is a finite language over Σ}
which of the following operation is not closed for L?

a. intersection

b. union

c. complement

d. none of the above



I thought the ans as d as all finite languages are regular and since regular languages are closed under all hence d seemed apt to me. But ans given is C 
which is correct C or D? and Why?
There are infinitely many strings over any alphabet, so if you pick any finite language, there are infinitely many strings not in it. In other words, there are infinitely many strings in the complement of any finite language.