Which statement accurately explains the data on this graph?
The US population increased at an even, upward rate from 1800 through 2000.
The US population increased slowly at first, then sharply during the twentieth century.
The US population experienced several ups and downs during the two centuries shown.
The US population was unchanged in the 1800s and only began to increase during the 1900s.
The correct statement is: The US population increased slowly at first, then sharply during the twentieth century.
### Explanation:
Historically, the US population growth began gradually in the early years of the nation but accelerated significantly during the 20th century due to factors such as improved healthcare, immigration, and higher birth rates. This trend reflects the population dynamics commonly seen in demographic studies. If you have further details or specific data from the graph you’d like to discuss, feel free to share!