A. Choose and encircle the letter of the correct answer on the answer sheet. 1. Which soil is the best for plants? A clay B. bedrock C. loam D. sand 2. Topsoil is the uppermost layer that is rich with organic materials called A. humus B. parent rock B. sub-soil D. bedrock 3. What layer of the soil is made up of undisturbed large boulders and gravel? A. humus B. parent rock B. sub-soil D. bedrock 4. Which soil is a mixture of sand and clay? A, sand B. sub-soil C. loam D. clay 5. Which of the following is the located below the topsoil? A. sand B. sub-soil C. loam D. clay 6. Which of the following is composed of rocks that are slowly breaking apart? A. humus B. parent rock B. sub-soil D. bedrock 7. It covers most of the land rt of the earth. A. Soil B. Air C. Fire D, Water 8. It is quite sticky since there is not much space between the mineral particles, and it does not drain well at all. A. sand B. sub-soil C. loam D. clay​