d. -24a³b⁷ is the correct answer.
1. You had to remove parenthesis first.
[tex]-3a^2b^4*8ab^3[/tex]
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2. Then you multiply by the numbers.
3*8=24
[tex]-24a^2ab^4b^3[/tex]
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3. Next you had to used apply exponent rule.
[tex]=-24a^3b^4b^3[/tex]
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4. And finally apply exponent rule again. It gave us the final answer.
[tex]=-24a^3b^7[/tex]
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Hope this helps! And thank you for posting your question at here on brainly, and have a great day. -Charlie
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