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The dashed line in the figure is equidistant from two positively charged plates. A small positively charged object is placed at point $\displaystyle {P}$ and released from rest. Assuming gravitational effects are negligible, which of the following correctly predicts how the kinetic energy of the object will change, if at all, after it is released?

The kinetic energy of the object will increase suddenly and then decrease because the magnitude of the electric field along the dashed line decreases with increasing distance from the plates.
The kinetic energy will quickly achieve a constant value because the magnitude of the electric field along the dashed line is constant.
The kinetic energy of the object will continue to be zero because the electric field at point $\displaystyle {P}$ is zero.
The kinetic energy of the object will begin to increase and continue increasing because the electric field along the dashed line is nonzero and directed to the right for all finite distances from the plates.

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