Answer:
B, C,
Step-by-step explanation:
A - This is addition. Finding a product refers to multiplication, so this is not correct.
B - This is multiplication of 5x × 5y, exactly two factors, so this is correct.
C - This is multiplication of (x-y) × (x+y). Each equation inside the parenthesis equals one factor, so this is multiplication of exactly two factors. This answer is also correct.
D - This is multiplication of three factors, x × y × z, and is not correct.
