Consider consecutive processes A$-->$B$-->$C$-->$D$,$ where process A has a capacity of $0\mathrm{.}7$ units per minute, $B$ has a capacity of $50$ units per hour, $C$ has a capacity of $52$ units per hour, while process D has a capacity of $0\mathrm{.}8$ 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.

After process D

In front of process A

In front of process D

In front of process $C$

In front of process B