Consider a production line with five stations. Station I can produce a unit in 18 minutes. Station 2 can produce a unit in 20 minutes. Station 3 has two identical machines, each of which can process a unit in 24 minutes (each unit only needs to be processed on one of the two machines). Station 4 can produce a unit in 21 minutes. Station 5 can produce a unit in 16 minutes. Which station is the bottleneck station? O a. Station 2 O b. Station 4 O c. Station 5 O d. Station 1 O e. Station 3