Answer:
Continental polar masses are likely to occur.
Explanation:
As you may already know, northern Canada and Greenland are regions close to the north pole. In these regions and in January, in the middle of winter, continental polar air masses are likely to occur.
Polar air masses originate in high altitude regions, such as northern Canada and Greenland, in addition, this type of mass usually occurs in regions near the poles. Polar air masses can be continental or oceanic, continental ones are cooler and drier, similar to the climate observed in this region in January. Oceanicas, on the other hand, are more humid and hot.