Refer to the table below. At what consumption level for this product does diminishing marginal utility set in$?$

$\backslash$begin$\{$tabular$\}\{|$c$|$c$|\}$

$\backslash$hline Number of Units & Total Utility $\backslash \backslash$

$\backslash$hline $3$ & $35\backslash \backslash$

$\backslash$hline $4$ & $80\backslash \backslash$

$\backslash$hline $5$ & $150\backslash \backslash$

$\backslash$hline $6$ & $252\backslash \backslash$

$\backslash$hline $7$ & $350\backslash \backslash$

$\backslash$hline $8$ & $440\backslash \backslash$

$\backslash$hline

$\backslash$end$\{$tabular$\}$

$4$ units

$5$ units

$6$ units

$7$ units