The African Maasai have adopted the Living Wall project in their bid

Official explanation
Meaning Analysis
• The African Maasai have adopted the Living Wall project in their bid to save their livestock from attacks by predators;
• the natural fences built of myrrh trees have been designed to prevent the attacks,
• and they do.
The sentence talks about the African Maasai who have taken up the Living Wall Project. They have taken up this project in an attempt to save their livestock from predators’ attacks. The next part of the sentence elaborates on the Living Wall Project. These Maasai build natural fences of the myrrh tree. These fences have been designed to prevent the predators’ attacks and are successful in preventing them.

Error Analysis
• Since all the actions pertain to the present context, all the tenses have been correctly used.
o The use of the present perfect tense verb “have adopted” is correct because this action started sometime in the past and is still taking place.
o The verb “have been designed” is correctly written in present perfect tense as the action was done sometime in the past but the effect is felt in the present.
o The simple present tense verb “do”, which stands for “prevent”, correctly presents a general fact in the present context.
• The modifiers are worded and placed correctly.
• This sentence has no errors.

Answer Choice Analysis

Choice A
Correct
• This choice has no errors as already pointed out in the error analysis.
Choice B
Incorrect
• The verb-ed modifier “designed” illogically modifies the preceding noun entity “myrrh trees”. It should modify “natural fences”.
• The present perfect tense verb “have been” incorrectly refers to the simple present tense verb “prevent.” Helping verb “do” should be used to refer to “prevent”.
Choice C
Incorrect
• This choice repeats the present perfect verb tense error of Choice B.
• The list containing two verbs “are designed” and “have” has been connected using comma + and. Whenever a list contains two elements, only and should be used to connect them.
Choice D
Incorrect
• The phrase “naturally built fences” is not the same as “natural fences”. The former means the fences that are built naturally. But the term “natural fences” means they are built of natural material.
• The pronoun “it” does not have any logical antecedent in the sentence. It should be replaced by “they” to correctly refer to the plural noun “fences.”
• Use of the simple present tense “is” is incorrect because it must be followed by the verb “prevented”. But this word is not present in the sentence.
Choice E
Incorrect
• This choice repeats the “naturally built fences” meaning error of Choice D.
• Use of present continuous tense “are being designed” is incorrect because it is not a continuous action. According to the intended meaning of the sentence, the fences have already been designed.