| <element name="base" | 
 | xmlns="http://relaxng.org/ns/structure/1.0"> | 
 |   <choice> | 
 |     <group> | 
 |       <element name="data">  | 
 |         <value>firstValue</value> | 
 |       </element> | 
 |       <oneOrMore> | 
 |         <element name="option"> | 
 |           <element name="value"> | 
 |             <text/> | 
 |           </element> | 
 |           <element name="label"> | 
 |             <text/> | 
 |           </element> | 
 |         </element> | 
 |       </oneOrMore> | 
 |     </group> | 
 |     <group> | 
 |       <element name="data">  | 
 |         <value>secondValue</value> | 
 |       </element> | 
 |       <oneOrMore> | 
 |         <element name="option"> | 
 |           <element name="value"> | 
 |             <text/> | 
 |           </element> | 
 |           <element name="label"> | 
 |             <text/> | 
 |           </element> | 
 |         </element> | 
 |       </oneOrMore>             | 
 |     </group> | 
 |   </choice> | 
 | </element> |