Final answer:
The expression 7x + 2y is the sum of two products, consisting of two terms, which aligns with the commutative property of addition.
Step-by-step explanation:
The expression 7x + 2y represents a linear algebraic expression and it can be best described as the sum of two products. Here, 7x is the product of 7 and x, and 2y is the product of 2 and y. When these two products are added together, we get the expression 7x + 2y. This expression contains two terms.
Therefore, the correct answer to the question is: A. The sum of two products; there are two terms. This is further reinforced by the algebraic principle where the order of addition does not affect the sum, expressed as A+B=B+A. This is also known as the commutative property of addition.