On which of the following is there a tax incentive in the United States?

$($i$)$ health insurance purchased through employers

$($ii$)$ employer contributions for life insurance

$($iii$)$ rental value on owner$-$occupied housing

$($iv$)$ your mortgage

$($iv$)$ only

$($i$),($ii$),($iii$),$ and $($iv$)$

$($iii$)$ and $($iv$)$

$($i$),($iii$),$ and $($iv$)$