contestada

The following binomials are multiplied together as shown below. Which of the following is a true statement?
(x+y)(a+b)
= xa+xb+ya+yb
A. There is no error; the binomials were correctly multiplied together.
B. Binomials with different variables cannot be multiplied together.
C. The product was not simplified correctly.
D. There should only be three terms when multiplying two binomials.