Suppose the Federal Reserve Bank of Chicago's National Activity Index

Suppose the Federal Reserve Bank of Chicago's National Activity Index hovered around +0.25 for a few months and then dropped to -1.5 in November.Which of the following is the best interpretation of this finding?

A) The economy grew at a rate of 0.25% for a few months,but economic growth actually decreased by 1.5% in November.
B) The rate of economic growth slowed in November,but the economy did not move into a recession.
C) The economy was in an expansion in October but moved into a recession in November.
D) Economic activity was above the historical trend rate of growth,but it is likely that the economy moved into a recession in November.