Look at this graph from When Birds Get Flu and Cows Go Mad! by John DiConsiglio. HIV/AIDS IN AFRICA, 1958–2003

The deadly disease has been dramatically shortening life expectancy.

A graph shows years labeled 1958 to 2003 on the x-axis and life expectancy labeled 30 to 65 on the y-axis. There is a line for each country. All lines show an upward trend from 1958 to the 1980's and a downward trend from the 1980's to 2003.

Given the change in life expectancy, what can the reader conclude about HIV/AIDS in Africa?

It has spread over time.
It has lessened over time.
It has been wiped out over time.
It has stayed the same over time.