The point where the curve changes from concave upward to concave downward (option B)
Step-by-step explanation:
The inflexion point of a curve on a graph is referred to as the point where the concavity changes.
In other words, the function on the graph changes from a concave up to concave down or from a concave down to a concave up. It can be determined at the point where the second derivative changes its sign.
Since the bell shape is a curve, the inflexion point will be the point where the curve changes from concave upward to concave downward (option B)