Let $$S$$ be the set of positive integral values of $$a$$ for which $$\frac{ax^2 + 2(a+1)x + 9a + 4}{x^2 - 8x + 32} < 0, \forall x \in \mathbb{R}$$. Then, the number of elements in $$S$$ is:

A

1

B

0

C

$$\infty$$

D

3