Why were rivers important for the growth of cities?

 Rivers are used for a source of water, for food, for transportation, and a defensive barrier, and disposing waste.

Explanation:   There are many reasons rivers are important to cities. Rivers have been used as a source of water, for food, for transport, as a defensive barrier, and also as a means of disposing of waste.

the answer is c.

i hope this .

seeing as no choices were provided, i'll do my best to answer it from knowledge.

job specialization promotes work ethic to the person doing the job. he/she may be strong in the arms and able to lift things, specializing him/her in a job where you lift and carry.