The correct answer is D. Smoothing.
Smoothing is a technique used to reduce noise in a signal. It does this by averaging the values of neighboring points in the signal. This can be done by taking the average of the values of the points within a certain window, or by using a moving average filter.
Specular reflection is a type of reflection that occurs when light hits a smooth surface and is reflected back in a single direction. Diffuse reflection is a type of reflection that occurs when light hits a rough surface and is reflected in all directions. Gaussian filter is a type of filter that is used to smooth out noise in an image. It does this by averaging the values of neighboring pixels.
In the context of the question, predicting the value of a state variable from the past is a type of smoothing. This is because it involves averaging the values of neighboring points in the time series. This can be done by taking the average of the values of the points within a certain window, or by using a moving average filter.
For example, let’s say we have a time series of temperature data. We can use a moving average filter to smooth out the data. This will result in a new time series that has lower noise. The new time series will be a better representation of the underlying trend in the data.