The correct answer is - It is released from a transporting medium.
The deposition process in essence means that a sediment that is transported by a certain medium is released at a certain place and creates deposits of the sediment.
The deposition can be done by multiple mediums, such as the streams and rivers, mud-flows, landslides, heavy rainfall, glaciers... The principle of making a deposit is the same in each of them, but the way of transportation is a bit different at some of them. The rivers and streams are carrying sediments while they are faster, but when they start to lose their speed, they are not able to carry its weight anymore, so they release it. The glaciers are using their sheer force and they are pushing the sediments to the place where they are melting. The heavy rainfalls, mud-flows, landslides, are transporting the sediments in a very rapid manner, usually over shorter distances, and it is always from a steeper part towards a flatter part.
