Which of these always remains unchanged over time? the understanding of how diseases affect people
the way in which diseases are treated
the number of people who have diseases
the causes of human diseases

your answer is 1930's

explanation

this is just around the time the great depression was starting and putting the us ecnomy into ecnomic failure causing the goverment to take a much larger rule to try and pieace it back together

c) all of the above

mutation is when you body morphs to something odd or bad looking (no offense)