Three point charges are fixed along the \(x\)-axis: a charge \(-2q\) is located at the origin, and two charges each of charge \(+q\) are located at \(x = -d\) and \(x = +d\). Point \(P\) lies on the positive \(y\)-axis at a distance \(y\) from the origin. Which of the following expressions represents the magnitude of the net electric field at point \(P\) in terms of given quantities and fundamental constants?