[問題]FeiFei Q70

[dianechiu]

70. A low-pressure weather system is approaching Plainville; rainfall results from about 70 percent of such systems in the Plainville area. Moreover, the current season, spring, is the time of year in which thundershowers, which sometimes result from low-pressure systems, are most likely to occur in Plainville.

Knowing which one of the following, in addition to the information above, would be most useful for determine the probability that Plainville will have a thundershower soon?

(A) the percentage of thundershowers in Plainville that occur in the spring
(B) the percentage of spring rainfalls in Plainville that are thundershowers
(C) the percentage of thundershowers in Plainville that result from low-pressure systems
(D) whether low-pressure systems in other areas are associated with rainfall
(E) whether Plainville has more or fewer thundershowers each spring than do near by towns

我得到的解答有兩個版本(B)or(C)
本來在寫的時候直覺寫(C),因為才跟低氣壓系統有關係
後來檢討,又覺得(B)比較好才可能性才算得出來
想法如下:
(B) the percentage of spring rainfalls in Plainville that are thundershowers
(春季雷陣雨發生在P地春雨的比率=>P地:春季雷陣雨/春天降雨)
(C) the percentage of thundershowers in Plainville that result from low-pressure systems
(來自低氣壓系統的雷陣雨發生在P地雷陣雨的比率=>P地:低壓系統雷陣雨/雷陣雨)

不知道大家看法如何,謝謝

[dibert8]

覺得 thundershower 和 rainfall 無關: "thundershowers, which sometimes result from low-pressure systems"
從 rainfall 去算 thundershower 應該會漏掉一些機率吧! (i.e. 從 low-pressure 但不是從 rainfall 造成的 thundershower)
=> (C)