Clear check list

Dear Support

For my users in I am modifying the drop down list to only give the correct country as below. However, the country Vietnam does not add automatically and the users still have to manually select.

Is there any way that I can script it so the country Vietnam is the only option?

Regards

Peter

b = zoho.loginuser;
if (b.contains("viet"))
{
clear Country;
Country.add("Vietnam");
input.wUser = "moanazoho";

.......... etc etc
moanazoho