Match the expressions of column I with that of column II:
Column I | Column II |
(1) `(21x + 13y)^2` | (a) `441x^2 – 169y^2` |
(2) `(21x – 13y)^2` | (b) `441x^2 + 169y^2 + 546xy` |
(3) `(21x – 13y) (21x + 13y)` | (c) `441x^2 + 169y^2 – 546xy` |
| (d) `441x^2 – 169y^2 + 546xy` |