Final answer:
The expression (x^2 + 4)(y^2 + 9) is misaligned with the concept of difference of two squares and none of the given options correctly reformulate it into a Two Squares expression. Expansion yields x^2y^2 + 9x^2 + 4y^2 + 36.
Step-by-step explanation:
The expression (x^2 + 4)(y^2 + 9) does not directly lend itself to a difference of two squares since both terms being added in each parenthesis are positive. However, if one is looking to rewrite this without fundamentally changing the expression into a format involving squares, none of the options a, b, c, or d provided is correct.
The correct reformatting would involve expanding the brackets, resulting in x^2y^2 + 9x^2 + 4y^2 + 36. This does not simplify to a concise format involving squares. As such, none of the provided options accurately represent the Two Squares reformation of the original expression.