Jacob qualified for an exemption from withholding in $2023.$ He also qualifies for an exemption from withholding for $2024.$ How does he inform his employer?

He can inform his employer by letter of his exemption.

He must complete Step $1$ only of Form W$-4,$ Employee's Withholding Certificate.

He must submit Form W$-4,$ Employee's Withholding Certificate, and write "Exempt" on the form in the space below Step $4($c$)$ and complete Steps $1($a$),1($b$),$ and Step $5.$

Since he already qualified in $2023,$ no further action is required on his part.