Yes, this model is made in Japan. Official information indicates that the A159W series has been produced at Casio's Yamagata factory in Japan since 1989, and specific data sheets mention "JAPAN" as the country of origin for related models. Although the exact identifier "zd168a" is not explicitly referenced in the available data, the technical specifications and manufacturing designation correspond to the A159W range manufactured in Japan.
For further confirmation, I recommend checking the "Made in Japan" inscription on the back of the case, present on models in this series. The internal data provided does not contain any contradictory information regarding the manufacturing origin.
If in doubt, consult the official documentation supplied with the watch or contact your local Casio customer service for accurate verification of the serial number.