lOrg and lRepPer are Named Ranges, used here because Data Validation doesn't allow using Table references (You get error, when you replace e.g. =lOrg with =tOrg[OrgName] in Data Validation Source. The same happens with Conditional Formatting, but when I remember correctly, with Conditional Formatting Names don't work also - you can use only cell references).

To see all defined Named Ranges (and defined Tables, ODBC Query dataranges, defined Print Areas etc.), select from Menu Formulas and open Name Manager. To see how a name listed in Name Manager is defined, select a name and then Edit (some objects listed in Name Manager, like defined Tables, you can't edit here).

Here I used my own naming convention for Named Ranges. Names beginning with "n" are usually Named Values (like nPI = 3,14...), or fixed Named Ranges (like nName = Sheet1!$A$1 or nName = Sheet2!$A$2:$X$10000). Names beginning with "d" are dynamic Named Ranges (like dName = OFFSET(Sheet1!$A$1,1,,COUNT(Sheet1!$A:$A),10) or dName = tTable). And a specific group are single column dynamic Names defined for using as Data Validation List sources - those are beginning with "l" like ones used here. The reason is, that so are Names grouped in Name Manager. Sometimes I have some 30-40 different names defined for workbook, and it is annoying to search for them over whole Name Manager.