Patterns of indicate how age at death influences population size:
a. death rate
b. age structure --b is not it i know that
c. survivorship
d. logistic growth

The answer is A. Patterns of death rate indicate how age at death influences population size. death rates are used to see how many individuals die for a specific age group.  Death rates depend on the variance of age-of-death wherein, consequently, affects the population growth rate which is linked to the distribution of age at death.