Which is a density-dependent factor?

Density-dependent factor affects population size.

Explanation:

Density-dependent factor can be defined as factor that affects population growth rate by increasing or decreasing birth and death rates in a way that directly affects the population density.

Density-dependent factors include:

Competition

Parasitism

Predation

Disease

25teer 4tfsyeg a r   drgfenr5s srg sawze sraeg rsew r

your answer is "the 1950's"