Dried grass clippings mixed into garden soil gradually decompose, providing nutrients for beneficial soil bacteria. This results in better-than-average plant growth. Yet mixing fresh grass clippings into garden soil usually causes poorer-than-average plant growth. Which one of the following, if true, most helps to explain the difference in plant growth described above? (A) The number of beneficial soil bacteria increases whenever any kind of plant material is mixed into garden soil. (B) Nutrients released by dried grass clippings are immediately available to beneficial soil bacteria. (C) Some dried grass clippings retain nutrients originally derived from commercial lawn fertilizers, and thus provide additional enrichment to the soil. (D) Fresh grass clippings mixed into soil decompose rapidly, generating high levels of heat that kill beneficial soil bacteria. (E) When a mix of fresh and dried grass clippings is mixed into garden soil, plant growth often decreases.
will provide the oa after discussion , please post your timing too
_________________ What is of supreme importance in war is to attack the enemy's strategy.
Dried Grass Clippings in Soil = Nutrients for Beneficial Bacteria = Better than Average. But Actual Crop poorer than average when fresh mixed with soil.
Pre-phrase : Maybe the grass clippings provide growth for non beneficial bacteria or maybe something happens to beneficial bacteria
A/Cs: (1)Does not solve the paradox, confuses it more (2)Same as above (3)Same as above (4)Solves paradox by saying that bacteria die = poorer than average results (5)Mix of Fresh and Dried is out of scope. We are bothered about only fresh or only dried.
Answer is (D)
_________________ GMAT done - a mediocre score but I still have a lot of grit in me
As i read through the options, I held B as an option, but clearly D is superior. B has a "so what?" element to it, until we know something about the fresh clipping and it's bacteria it does not aid in resolving the paradox.
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Dried grass clippings mixed into garden soil gradually decompose, providing nutrients for beneficial soil bacteria. This results in better-than-average plant growth. Yet mixing fresh grass clippings into garden soil usually causes poorer-than-average plant growth.
We already know why the dried grass clipping helps the growth. We are just concerned about why the fresh grass clippings adversely affect the growth.
Which one of the following, if true, most helps to explain the difference in plant growth described above? (A) The number of beneficial soil bacteria increases whenever any kind of plant material is mixed into garden soil. This is suggesting that irrespective of its state, the grass clipping should have added to the growth. However, we know exactly the opposite happened. We need to find why it happened and this statement is taking us in opposite direction.
(B) Nutrients released by dried grass clippings are immediately available to beneficial soil bacteria. Alright!! This is under the hood explanation of why the growth happened with dried grass clipping. Couldn't you tell me why it did not happen with the fresh clippings. Useless.
(C) Some dried grass clippings retain nutrients originally derived from commercial lawn fertilizers, and thus provide additional enrichment to the soil. Again!!! Same as B. Gives us a reason why the growth happened with dried grass. Furthermore, it is more restrictive in saying that this happens only for SOME dried grass. We're talking about all dried grass clipping here. Worse than B.
(D) Fresh grass clippings mixed into soil decompose rapidly, generating high levels of heat that kill beneficial soil bacteria. Couldn't you be at A? Yes, this is exactly what we wanted to know, ain't? It is providing us with perfect explanation about the deterioration in growth. The fresh grass clipping killed the bacteria aiding the growth of the plant. Oh yea!!! It will surely adversely affect the growth. Correct.
(E) When a mix of fresh and dried grass clippings is mixed into garden soil, plant growth often decreases. What is the proportion in which it will be mixed. Again, I can guess this would be due to the fresh grass clippings. But, why would it happen. If you can't explain WHY... get away from me.
will provide the oa after discussion , please post your timing too