The following sequence shows four operations steps for an ECG lead wire assembly process and the effective capacity of each. Which step has a bottleneck? Cutting: $1,500$ wires$/$hour$,$ Stripping: $1,450$ wires$/$hour$,$ Soldering: $1,500$ wires$/$hour$,$ and Over molding: $1,500$ wires$/$hour$.$

A$.$ Cutting

B$.$ Stripping

C$.$ Soldering

D$.$ Over molding