What is the effect of the Welland Canal on shipping routes?

The Welland Canal serves a crucial role in facilitating shipping by providing a navigable route that allows ships to bypass the challenging waters of Niagara Falls. This connection between Lake Ontario and Lake Erie significantly enhances transportation efficiency, as ships can travel directly without needing to contend with the natural barriers posed by the falls. Not only does the canal enable larger vessels to move freely between these two major Great Lakes, but it also plays a vital role in international trade and commerce, ensuring that goods can be transported year-round without disruption by the falls.

The other options don't accurately reflect the primary function of the Welland Canal. The canal does not connect Lake Ontario to Lake Michigan; instead, it connects to Lake Erie. Additionally, the well-being of shipping in winter months is influenced by ice conditions, rather than any particular characteristic of the canal itself, and while there are tolls associated with the use of the canal, the statement regarding increases is not a direct outcome of the canal's primary function.