D. The reason for the fall of the Maya civilization is still unknown. There are many different theories attempting to explain the cause of the Classic Maya collapse and the abandonment of Maya cities in the southern Maya lowlands of Mesoamerica between the 8th and 9th centuries: climate change, drought, deforestation, etc. but although the drought is the leading theory at the moment the truth is yet unknown.
<u>Answer:</u>
The correct answer option is B. Soldiers gathered together in camps by the river.
<u>Explanation:</u>
Out of the given possible answer options, we are to determine whether which of the sentence has an intransitive verb.
Option B is the correct answer.
Soldiers gathered together in camps by the river.
Here in this sentence, the word 'gathered' serves as an intransitive verb as it is a complete, independent sentence and does not need any object.
The correct answer choice would be B.
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