11. All of the following statements concerning Polar Front Theory of a developing mid-latitude cyclone are correct, EXCEPT:
A secondary lows occasionally develop at the triple point of a mid-latitude cyclone
B mid-latitude cyclones are most intense in the advanced occlusion stage of development
C a series of mid-latitude cyclones exist along the polar front at any given time
D In the US, mid-latitude cyclones often form over the Gulf of Mexico