Answer: Option (A) is the correct answer.
Explanation:
When a substance like sand gets carried away along with the flow of wind then this process is known as erosion.
When a substance is kept in air for too long and this exposure causes change in appearance or texture of the substance then it is known as weathering.
When rocks gets deposited on a land then this is known as deposits rocks on.
Thus, we can conclude that when Sam blew out through a straw and directed his breath at a pan of sand. Sam is showing the rest of his class how the wind erodes the land.
