The function y = X squared + 3 is a transformation of the function y = x2. How is the y-intercept of the function affected by the transformation?

1. The y-intercept of the graph of y = x2 is shifted down 3 units.
2. The y-intercept of the graph of y = x2 is shifted to the left 3 units.
3. The y-intercept of the graph of y = x2 is shifted to the right 3 units.
4. The y-intercept of the graph of y = x2 is shifted up 3 units.