a. oceans are an important source of food in japan b. terrace farming is used in many parts of china ... which conclusion can best be drawn from these statements?

China and Japan get most of their food through national agriculture.

Explanation:

With the statements made in the question, we can conclude that China and Japan get most of their food through local agriculture, unlike some countries that need to import most of the necessary agricultural products needed for food.

With the statements made in the question, we can conclude that China and Japan get most of their food through local agriculture, unlike some countries that need to import most of the necessary agricultural products needed for food.

With the sentence of letter B, we can conclude that China has been using agricultural practices to optimize its production of agricultural products, avoid waste, prevent soil loss through erosion and optimize the use of agricultural land.