Consider consecutive processes A$-->$B$-->$C$-->$D$,$ where process A has a capacity of $0\mathrm{.}5$ units per minute, $B$ has a capacity of $26$ units per hour, $C$ has a capacity of $23$ units per hour, while process D has a capacity of $0\mathrm{.}45$ units per minute. According to the Theory of Constraints, where would an operations manager want to have an inventory buffer?

Assume that market demand exceeds available capacity.

In front of process D

In front of process B

In front of process $C$

In front of process A

After process D