Artificial selection to obtain cows yielding higher milk output represents

Stabilizing selection as it stabilizes this character in the population

Directional as it pushes the mean of the character in one direction

Disruptive as it splits the population into two one yielding higher output and the other lower output

Stabilizing followed by disruptive as it stabilizes the population to produce higher yielding cows

Answer

Directional as it pushes the mean of the character in one direction

Artificial selection to obtain cow yielding higher milk output will shift the peak to one direction, hence, will be an example of Directional selection. In stabilizing selection, the organisms with the mean value of the trait are selected. In disruptive selection, both extremes get selected.