Please choose the correct answer to the question: Some events on Earth happen instantly while others take thousands of years to occur. Which process takes the longest time to complete?

Answer1: rivers rising due to storms and floods Answer2: evaporation of water from the leaves of a plant Answer3: weathering of a rock to form small rocks and sand Answer4: movement of small pieces of rock by flowing water

Answer format: answer1/answer2/answer3/answer4
Answer: answer3