A pair of parametric equations is given: ( x = t², , y = t⁴ + 3 ).
Find a rectangular-coordinate equation for the curve by eliminating the parameter.
a) ( y = x² + 3 )
b) ( y = x⁴ + 3 )
c) ( y = x² - 3 )
d) ( y = x⁴ - 3 )