Beginner solution | Easily Understandable
\tSELECT name FROM SalesPerson WHERE sales_id not in\n\t(\n\t\tSELECT sales_id  FROM Orders WHERE com_id not in\n\t\t(\n\t\t\tSELECT com_id FROM Company WHERE n
\tSELECT name FROM SalesPerson WHERE sales_id not in\n\t(\n\t\tSELECT sales_id  FROM Orders WHERE com_id not in\n\t\t(\n\t\t\tSELECT com_id FROM Company WHERE name<>"RED"\n\t\t)\n\t);
[]