15. Worldwide demand for more _____ technology continues to grow.

A. subtle B. experienced C. sophisticated D. refined

sophisticated 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