Answer
The LCM is $120$. The number $240$ is a multiple of $120$ and cannot be the LCM of $8, 3, 5, 4, 10$.
Work Step by Step
$3 = 3$
$5 = 5$
$4 = 2 \cdot 2$
$8 = 2 \cdot 2 \cdot 2$
$10 = 2 \cdot 5$
LCM $= 2 \cdot 2 \cdot 2 \cdot 3 \cdot 5 = 120$.