A small outside force or effort at the _____ _______ on the object can change its condition from static to unstable equilibrium.

The scenario described involves the concept of equilibrium in physics, specifically static and unstable equilibrium. An object is said to be in static equilibrium when it is at rest and experiencing balanced forces. However, this equilibrium can be disrupted with the application of a small external force.

The correct choice indicates a position where a small force can create a significant change in the object's state. At the highest point of an object, especially in cases like a pendulum or a balanced object, any small disturbance can lead to a shift away from that balance point. Once this balance is upset, the object can easily begin to rotate or fall, indicating a change from static to unstable equilibrium.

Understanding that the highest point is particularly sensitive to external forces helps clarify why this answer is the most accurate. In contrast, the lowest point or the center of mass would generally provide more stability, while the support base would often be related to the stability of the object but not necessarily to the transition from static to unstable equilibrium.