15. Worldwide demand for more _____ technology continues to grow. A. subtle B. experienced C. sophisticated D. refinedsophisticated 复杂的、久经世故的subtle 巧妙的、黯宛的、不明显的、不显著的、细微的、精细的sob 哭泣sorrow 痛苦experienced 有经验的refine 提炼、提纯define 下定义、有限的indefinite 无限的、不确定的confine 限制affinity 亲密