Final answer:
Increased employment opportunities for epidemiologists are driven by the rise in infectious diseases, the greater need for disease prevention, and the heightened importance of public health awareness due to the effects of global population density, travel, and emerging zoonotic diseases. Hence, options A, B, and C are correct.
Step-by-step explanation:
The expected increase in employment opportunities for epidemiologists can be attributed to a combination of factors, including the increase in infectious diseases, the increase in the need for disease prevention, and the increase in the need for public health awareness. As human populations grow and become more densely packed, the prevalence of infectious diseases rises, necessitating a larger workforce of epidemiologists to study, track, and devise strategies to combat these diseases.
Additionally, global travel facilitates the rapid spread of infections, making epidemiology crucial for international public health. The development of new zoonotic diseases (diseases that spread from animals to humans) further increases the demand for epidemiologists, who act as 'disease detectives' to contain outbreaks and inform public health measures.