GRE Reading Comprehension: ETS-GRE阅读ETS - 9_8S4X65XS7SH49R7

It can be inferred from the passage that the spreading out of lavas of different ages at hot spots indicates that a A. hot spot is active B. continental plate has moved C. continental rupture is imminent D. hot spot had been moving very rapidly E. volcano contains large concentrations of alkali metals