One study of 4 1/2 - to 6-year-old children in 10 american cities found that the children's rate of aggressiveness was influenced more by than by the amount of time they spent in day-care programs.

a) children's temperaments
b) parents' caregiving sensitivity
c) family's economic and educational levels
d) all of these factors

The correct answer is option D. all of these factors.

Explanation:

Aggressiveness rate in a child of 4 and a half to 6 years age, according to the study performed in 10 city is more than the amount of time they spent in daycare programs due to temperament of the child, caregiving sensitivity of parents and economic and educational levels of family.

Temperament is an innate quality of the child for most of the part but can also be acquired by experiences and can be positive or negative. The economical and emotional conditions of the family also affects the aggressiveness in the child.

Thus, the correct answer is option D. all of these factors.