3. In the table shown in Figure 1, if each cell is filled with a number such that each row forms an arithmetic sequence and each column forms a geometric sequence, then the value of $x + y + z$ is ( ).
(A) 1
(B) 2
(C) 3
(D) 4
3. A.

The last two numbers in the first and second rows are $2.5, 3$ and $1.25, 1.5$; in the third, fourth, and fifth columns, $x=0.5, y=\frac{5}{16}, z=\frac{3}{16}$. Thus, $x+y+z=1$.