When did the first economies begin to develop?
when all the hunter-gatherers died
when money was invented
when people began to grow crops and domesticate animals
when the first cities were built

When people began to grow crops and domesticate animals

Explanation:

The cultivation and domestication of animals were the first signs of the process of accumulation observed in primitive societies. Accumulation, in turn, gave rise to the surplus - when output was greater than the needs of the producer - and encouraged men to exchange their respective surpluses. Thus came the first evidence of economic development. When societies became a bit more complex, the need arose for the creation of currency to facilitate the exchange of surpluses.

is there multiple choice or do you need like an essay answer?

the factors that the economies of the muslim empires prosper were:

1- land trade routes-located between three continents  

2- sea trade routes

trade contributed to the spread of muslim empires, and with that islamic culture led to a growing feeling of internationalism resulted in the transfer of technology, science, and other cultural forms.