Please choose the correct solution to the question: Once you have filled a sinkhole with concrete and sand what additional steps can you take to stabilize it?

Solution1: Fill whatever depth remains to the sinkhole with topsoil. Finishing the hole with topsoil will allow plants to grow on top of the former sinkhole and stabilize the soil and sand.

Solution2: Fill whatever depth remains to the sinkhole with compost. Finishing the hole with compost will allow plants to grow on top of the former sinkhole and stabilize the soil and sand.

Answer format: solution1/solution2
Answer: solution1