Using the rule for Multiplication of integers.
In this question we have to multiply the first two integers and then from the answer that we get is multiplied with other integer,
={(-5$$\times$$ -8) $$\times$$ (-3)} ....[$$\because$$(-$$\times$$ - = +)]
={40 $$\times$$ (-3)} ...[$$\because$$(+$$\times$$ - = -)]
= -120
(In multiplication we have to multiply the sign of the integers also and then assign the obtained sign to the answer)