what was the effect of the Khmer farmers'surplus?

1) they bought more slaves
2) they earned great wealth
3) they enjoyed rainwater all the time
4) they explored the Pacific Ocean

#2 ?

That is correct.

They earned great wealth

The effect of the Khmer farmers' surplus was that they earned great wealth.

The effect of the Khmer farmers' surplus is directly related to their agricultural productivity and the resulting surplus of food. To determine the correct answer, let's analyze each option:

1) They bought more slaves: While slavery existed in ancient societies, there is no specific historical evidence or connection between Khmer farmers' surplus and increased slave ownership. Therefore, this option can be ruled out.

2) They earned great wealth: This option is likely the correct answer. When farmers have a surplus of crops, they can sell the excess and generate wealth. The additional income from selling surplus agricultural produce would have led to an increase in the economic prosperity of the Khmer farmers.

3) They enjoyed rainwater all the time: The availability of rainwater does not directly correlate with the Khmer farmers' surplus. While rainwater is essential for agriculture, its constant availability is not solely reliant on surplus production.

4) They explored the Pacific Ocean: The exploration of the Pacific Ocean is unrelated to the Khmer farmers' surplus. Exploratory voyages and maritime activities were not considered to be a direct consequence of agricultural productivity.

Therefore, the correct answer is option #2, which suggests that the Khmer farmers earned great wealth due to their surplus production.