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The ANSWER is A). The tidal pull of the moon.
See the article Tides in the Hudson River at this link
https://www.caryinstitute.org/sites/default/files/public/downloads/curriculum-project/tides.pdf
The citation from this article is below:
"Due to the topography of the landscape, enclosed bays can have tidal ranges of 20 or 40 feet!
The largest daily tide on the Hudson River is over 6 feet, while the smallest is under 3 feet.
The tides in the Hudson come from the rising and falling of the water at the mouth of the river, not the direct action of the moon."
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Good question, and the answer, which I found in the Internet, was unexpected to me . . .
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Added 2 hours later . . .
Regarding the "Black River", see this Internet page
https://tides.mobilegeographics.com/locations/591.html
The maximum tides are about 3 ft there.