* this method will return the <code>{@link IndexedElement}</code> "myOption" is pointing to.
* @param option the given option.
* @return the {@code Property} the given option is referring to, or {@code null} if it cannot be found.
*/
public IndexedElement rootSourceOf(AbstractOption option) {
OptionSource source = modelObjects.valueOfFeature(option, "source", OptionSource.class);
return source == null ? null : source.getTarget();
}