5. According to the Appellate Body in EC-Tariff Preferences (DS246), is the Enabling Clause an exemption from or an exception to the most-favourednation treatment obligation in Article I:1 of the GATT 1994? Does this characterisation diminish the right of Members to provide or to receive differential and more favourable treatment under the Enabling Clause? Which party bears the burden of proof in disputes regarding tariff preferences under the Enabling Cause?