Answer:
a) decreases and larger sediments are deposited first
Step-by-step explanation:
As the Niagara River enters the Lake Ontario, it is coming up to a large body of water that is stopping its flow as it enters in it. This results in a loss of velocity. Because the river losses its velocity, it is no longer able to carry the sediments with it, thus it starts to deposit them. The largest sediments are deposited first as they weigh the most, so the river needs greater velocity to transport them. As the velocity is becoming smaller and smaller, the medium sized sediments come next for deposition, and in the end are the smallest sediments that are deposited when the river totally losses its velocity.