The correct answer for the question is option 4, which is "Rearing of cattle and agriculture." Mixed farming refers to a type of farming system in which both crop production and livestock rearing are carried out simultaneously on the same farm. This practice helps to maximize the utilization of available resources and provides multiple sources of income for farmers. The combination of crop production and animal husbandry allows for a synergistic relationship, as the waste products from livestock can be used as fertilizer for crops, and the crops can provide feed for the animals. This integrated approach helps to enhance the productivity and sustainability of the farm. Therefore, option 4 accurately describes mixed farming.