Answer:
This is because many places in Europe, for example Germany had taken loans from the USA for their developmental plans. But as the Wall Street Exchange crashed, in September 1929, many European banks also collapsed. America's economy fell half by half and they stopped giving loans or any kind of financial support as they themselves were in crisis. This lead many European companies into bankruptcy and they could not pay the wages of workers. Thus, Europe was heavily impacted by the Great Depression.
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