Relationship between APC and APS in depicted by :

APC + APS = 1

The correct answer is option (4) : APC + APS = 1

The average propensity to consume (APC) is the proportion of total income that individuals or households spend on goods and services, while the average propensity to save (APS) is the proportion of total income that individuals or households save. Therefore, both APC and APS represent the utilization of income. 

Mathematically, the relationship between APC and APS can be stated as :

APC +APS =1

This equation holds because all income is either consumer or saved. Thus, the sum of the average propensity to consume and the average propensity to save equals 1.

Therefore, the correct option is (4) APC + APS = 1.