Make correct statements by filling in the symbols $\subset$ or $\not\subset$ in the blank spaces:
${ x:x \text{ is an even natural number} } \dots { x:x \text{ is an integer} }$

(A) Since every even natural number (e.g.,$2, 4, 6, \dots$) is also an integer,the set of even natural numbers is a subset of the set of integers.
Therefore,${ x:x \text{ is an even natural number} } \subset { x:x \text{ is an integer} }$.