The Local Health Department of a Small Town Has Hired

The local health department of a small town has hired a research firm to study the development of cancer in residents in the town due to a suspected cancer-causing agent and environmental pollution.The firm will examine data on participants at ages 10,then 20,then 30,and so on,to see if there are increasing rates of cancer in the town.This type of research study uses a _______ design.

A) cross-sectional
B) longitudinal
C) lifespan