GWD1-33没有人回答，所以另开一贴，感谢！

GWD1-Q33:

A company plans to develop a prototype weeding machine that uses cutting blades with optical sensors and microprocessors that distinguish weeds from crop plants by differences in shade of color.  The inventor of the machine claims that it will reduce labor costs by virtually eliminating the need for manual weeding.
            智能除草机能够减少劳动力成本

Which of the following is a consideration in favor of the company’s implementing its plan to develop the prototype原型?in favor of加强

1. There is a considerable degree of variation in shade of color between weeds of different species.

2. The shade of color of some plants tends to change appreciably over the course of their growing season.

3. When crops are weeded manually, overall size and leaf shape are taken into account in distinguishing crop plants from weeds.

4. Selection and genetic manipulation allow plants of virtually any species to be economically bred to have a distinctive shade of color without altering their other characteristics.

5. Farm laborers who are responsible for the manual weeding of crops carry out other agricultural duties at times in the growing season when extensive weeding is not necessary.—过渡引申

我的问题是：

对于E我还有一个问题，我觉得E是在说manual weeding of crops 啊？而文中不是在说distinguish weeds from crop plants by differences in shade of color那就说明 weeding of crop和weeding是两回事啊？那E中说不用weeding of crops而去做起他的农活，好像不是文章所说的吧。文中说的是不用weeding而节省劳动成本啊

所以，强烈请教各位NN，是不是我对weeding of crops的理解不对啊？

顶

怎么没人理啊？