Submarine sand deposits are abundant, ranging from precious diamonds, platinum sands, gold sands, to general cassiterite, magnetite, chromite, tungsten ore, and cheap grit debris, there are more than 20 kinds. Mining has become an important industry in Thailand, Indonesia, Malaysia and other countries. However, sand and gravel are the most mined from the shallow sea bottom, and the U. S. alone extracts more than 500 million tons. These gravels are used for glass. In addition to the production of ceramics and grinding wheels, they are mainly used as building materials. There are also some countries that use calcareous sand, shells, calcareous shale and other raw materials to produce cement from offshore shallow seabeds. The following summary is in line with the text? ['Almost all raw materials for industrial production are obtained from submarine sand deposits.', 'Mining of submarine tin mines has become a pillar industry in Southeast Asian countries.', 'The offshore shallow seabed has become a huge supply base of building materials.', 'Mining of sand and gravel in shallow seas is concentrated in the United States.']