#### Answer

true

#### Work Step by Step

RECALL:
$A \subseteq B$ if all elements of $A$ are also elements of $B$
The elements of $D$ are: $1, 2, 3$
The elements of $B$ are: $2, 4, 6, 8$
Since the elements of $D$ are not in $B$, then $D \not \subseteq B$ .
Thus, the given statement is true.