In a river, sand would most likely be carried by suspension.
Suspension is one of the 4 main processes of transportation in the river. Suspension happens when materials made up of very fine particles like clay or silt are carried or lifted as a result of the turbulent current in the river. Rivers that are fast-flowing and highly turbulent carry more suspended materials. One of these suspended materials is sand.
Rocks are the biggest on there pebbles are usually as big as a grape and sand even smaller ,but minerals are so small you need a magnifying glass to see them so minerals would be the correct answer. I did this on a Test.
