Final answer:
The occurrences of infectious disease increase as a society becomes more sedentary due to factors such as close human proximity, weakened immune systems, and global travel.
Step-by-step explanation:
The occurrences of infectious disease increase as a society becomes more sedentary. This is due to several factors, such as increased close human proximity, which allows for easier transmission of diseases. Additionally, sedentary lifestyles often lead to less healthy habits, such as poor nutrition and lack of exercise, which can weaken the immune system and make individuals more susceptible to infections. Global travel also plays a role in the spread of infectious diseases, as it allows carriers of diseases to transmit them to different parts of the world.