单选题12.As mainstream chip production technology shifts from one generation to the next every three to five years, plants with new technology can make more powerful chips at lower costs, ______ plants with outdated equipment, which often cost billions of dollars to build, will be marginalized by the maker.
【正确答案】
C
【答案解析】本题中空格处应填表示对比的主从连接词，因为plants with new technology与plants with outdated equipment：make more powerful chips at lower costs与will be margina—lized by the maker是对比关系，因此本题答案为C。