Answer
$\text{False}$
Work Step by Step
Given:
$U = \left\{1, 2, 3, 4, 5, 6, 7, 8\right\}$
$B = \left\{1, 3, 5\right\}$
$B'$ is the complement of $B$, which is a set that contains all the elements of $U$ that are not in $B$.
Note that $B'$ should have the elements $2, 4, 6,7, \text{ and } 8$..
The given $B'$ does not have the element $7$.
Therefore, the given statement is FALSE.
