请大家帮忙看看这个题目，我是被这个题目绕晕了。谢谢。

Because mining and refining nickels is costly,researchers have developed an alternative method for extracting nickels using Streptanthuspolygaloides, a plant that absorbs and stores nickel from the soil as it grows.The researchers incinerated a crop of Streptanthus

Which of the following, if true, most stronglysupports the conclusion that the use of Streptanthus to extractnickel will be commercially adopted?

A.     The season in which the researchers grew Streptanthuswas an unusually favorable one, with the right amount of precipitation tomaximize the growth rate of Streptanthus

B.      Because lowering the concentration ofnickel in the soil can make land much better for agriculture in general, a plotin which Streptanthus has been grown and harvested can be sold forsubstantially more than it cost

C.     More air pollution is generated for eachpound of nickel produced by extracting it from Streptanthus than isgenerated using conventional mining and refining

D.     The land on which the researchers planted Streptanthuswas unusually free of the various weeds that can compete with Streptanthus