.Banks accumulated a great deal of knowledge about plants and agriculture. In growing strawberries he went back to the abandoned ______ of spreading straw under the fruit to reduce the necessary amount of watering..

A. custom      B. approach   C. practice     D. principle

Banks accumulated a great deal of knowledge about plants and agriculture．In growing strawberries he went back to the abandoned       of spreading straw under the fruit to reduce the necessary amount of watering．

A．custom          B．approach         C．practice          D．principle