Which algebraic expression is represented by the model?

The figure shows a table, the heading of whose first column is a multiplication operator and the heading of the second column is a rectangular model which is divided into four portions. One portion represents x and each of the other three portions represent 1. In the first column, three rows are shown where each row has a square labeled as 1. In the second column, three rows are shown where each row has the same model as shown in the heading.

A. 3 (3x + 9)
B. 3x (x + 3)
C. 3 (x + 3)
D. 3 (x + 9)