Determine the Intersection $\boldsymbol { X } \cap \boldsymbol { Y }$

Multiple Choice

Determine the intersection $\boldsymbol { X } \cap \boldsymbol { Y }$ . Express the answer in interval notation.
- $X = \{ x \mid x \geq 18 \}$ and $Y = \{ x \mid x < 11 \}$

A) $[ 11,18 )$
B) $( - \infty , 11 ] \cup ( 18 , \infty )$
C) $( 11,18 ]$
D) { }