A sequence $$\left\{x_n \right\}$$ of real numbers is defined as follows:

$$x_0 = 1, x_1 = 2,$$ and $$x_n = \frac{1 + x_{n - 1}}{x_{n - 2}}$$ for n = 2, 3, 4 ...
It follows that $$x_{2018}$$ is

A

1

B

2

C

3

D

4