The CPI values for the past few months, in order, have been given as 150, 155, and 160. What do these values tell you about prices in the economy?(

Prices are perfectly stable.
There is disinflation. Prices are increasing at a decreasing rate.
There is deflation. Prices are increasing at a decreasing rate.
There is inflation. Prices are increasing at a constant rate.

There is inflation. Prices are increasing at a constant rate.