14. It is an irrigation system where water is applied and distributed by gravity over the surface of the soil. A. basin irrigation C. sprinkler irrigation B. drip or trickle irrigation D. surface irrigation 15. In areas where water is scarce, which of the following irrigation system is ideal? A. basin irrigation C. sprinkler irrigation B. drip or trickle irrigation D. surface irrigation 16. Which of the following type of plow being pulled by a four-wheel tractor? A. Native plow C. wooden plow B. disc plow D. none of these​