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

D In the US, mid-latitude cyclones often form over the Gulf of Mexico

Explanation:

From the polar front theory, it can be asserted that in the mid-latitude there exist a boundary of cold dry air CP to the north and warm moist air to the south. The mid-latitude cyclone that develops has a cyclic nature and develops in a clockwise direction in the northern hemisphere. Thus they have a difference between the hurricane and mid-latitude cyclone, the typical diameter of the mid-latitude trip[ocala cyclone is 1500-5000 km. Thus there is an intensity of cyclone at the occlusion stage as they are rich in moisture and can bring heavy snowfall. But they don't cross the North American border as they weaken when going southwards.