Please need a fast reply
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[tex]\sf \bf {\boxed {\mathbb {C. \: 21n + 7}}}[/tex]
[tex]\large\mathfrak{{\pmb{\underline{\red{Step-by-step\:explanation}}{\red{:}}}}}[/tex]
[tex]7 \: ( \: 3n + 1 \: )[/tex]
➼[tex] \: 21n + 7[/tex]
[tex]\large\mathfrak{{\pmb{\underline{\orange{Mystique35 }}{\orange{❦}}}}}[/tex]