The function graphed here is an exponential decay function.
Becasue an exponential decay function is characterized by a curve that starts in quadrant 2 and decreases as it moves into quadrant 1. It crosses the y-axis at a positive value and approaches y = 0 as it continues into quadrant 1. This behavior matches the description given in the question, so we can conclude that the function graphed is an exponential decay function.