Dried grass clippings mixed into garden soil gradually decompose, prov

Question

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.

Source: LSAT

Bunuel · Accepted Answer

Official Explanation Our goal in this problem is to find the agent that causes fresh grass clippings to generate poorer-thanaverage plant growth. Choice (A) contradicts the implication of the passage. If fresh grass clippings increase beneficial soil bacteria, then plant growth should increase, not decrease. Choice (B) explains why dried grass clippings increase plant growth but does not explain why fresh grass clippings decrease plant growth. A similar analysis shows that choice (C) is incorrect. Choice (D) gives us our agent—heat. https://gmatclub.com/forum/download/file.php?id=60545 The answer is (D). 2021-02-18_22-36-16.png

JarvisR · Answer

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.

aimtoteach · Answer

Hi, This was an easy one

The only option that 'explains the difference in plant growth' is D. A and E - are irrelevant as they talk about benefits of plant material mixing and the Fresh grass+ dried grass mix. Both are not B and C strengthen the reason to keep using dried grass but dont explain the reason for lack of growth with fresh grass. So if we focus on the question stem and look for a direct answer, we will reach D. Hope this approach is correct. Thanks, aimtoteach ------------ Looking for Kudos

Skywalker18 · Answer

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.

Type -explain the situation 
Pre-thinking -- Fresh grass clipping nullify the positive effect of dried grass clipping

(A) The number of beneficial soil bacteria increases whenever any kind of plant material is mixed into garden soil. -- Deepens the paradox

(B) Nutrients released by dried grass clippings are immediately available to beneficial soil bacteria. -- Irrelevant

(C) Some dried grass clippings retain nutrients originally derived from commercial lawn fertilizers, and thus provide additional enrichment to the soil.-- Irrelevant -- just provides a mechanism

(D) Fresh grass clippings mixed into soil decompose rapidly, generating high levels of heat that kill beneficial soil bacteria.-- Correct

(E) When a mix of fresh and dried grass clippings is mixed into garden soil, plant growth often decreases. -- We already know this

Answer D

Damion123 · Answer

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?

Dry Grass --> better-than-average plant growth
Fresh Grass --> poorer than-average plant growth.

Pre Thinking: There should be some factors involved that affect the growth of plant.

(A) The number of beneficial soil bacteria increases whenever any kind of plant material is mixed into garden soil.  No Help

(B) Nutrients released by dried grass clippings are immediately available to beneficial soil bacteria.  Ok but does not talk about fresh grass.

(C) Some dried grass clippings retain nutrients originally derived from commercial lawn fertilizers, and thus provide additional enrichment to the soil.  Ok but does not talk about fresh grass.

(D) Fresh grass clippings mixed into soil decompose rapidly, generating high levels of heat that kill beneficial soil bacteria.  Bulls Eye. That is promising. However let's see Option E as well

(E) When a mix of fresh and dried grass clippings is mixed into garden soil, plant growth often decreases.  Out of Scope. Irrelevant.

VerbalBot · Answer

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Dried grass clippings mixed into garden soil gradually decompose, prov

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