If x, y, and z are positive numbers satisfying$$
x+1 / y=4, \quad y+1 / z=1, \text { and } z+1 / x=7 / 3
then $x y z=$
**Answer Choices**
A. $2 / 3$
B. $1$
C. $4 / 3$
D. $2$
E. $7 / 3$
If x, y, and z are positive numbers satisfying$$
x+1 / y=4, \quad y+1 / z=1, \text { and } z+1 / x=7 / 3