$1$ point

$23.$ What is the maximum size copper bonding jumper for a metal water piping system installed for a building that is supplied by a $4,000$ ampere, $3-$phase, $4-$wire, $480\frac{Y}{277}-$volt service?

O$.6$ AWG copper or $4$ AWG aluminum or copperclad aluminum

Ob$.3/0$ AWG copper, $250$ kcmil aluminum or copperclad aluminum

Oc$.$ Not less than $12\mathrm{.}5\%$ of the largest ungrounded service conductor

d$.$ Not less than the size required by $250\mathrm{.}122$ using the rating of $4,000$A overcurrent protective device

$1$ point