This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Fluid and Electrolyte Treatment of Specific Disorders, Subject name: Pediatrics
Which of the following inherited disorders is a Potassium Channelopathy? 
Select and explain. 
A. Hyperkalemic periodic paralysis, B. Hypokalemic periodic paralysis, C. Beckers's disease, D. Anderson Tawil syndrome
D: Anderson Tawil syndrome
Answer: D: Anderson Tawil syndrome 
Explanation: d. Anderson Tawil syndrome(Ref: Harrison's 19/e p 462)Channelopathies are progressive syndromic cluster of symptoms not localizing to single lesionImportant Channelopathies: (All of these are autosomal dominant & show episodic weakness)FeatureCalcium ChannelSodium ChannelPotassium ChannelHypokalemic PPHypokalemic PPParamyotonia CongenitaAndersen-Tawil syndromeAge of onsetAdolescenceEarly childhoodEarly childhoodEarly childhoodMyotoniaNoYesYesNoFrequency of attacks of weaknessDaily to yearlyMay be 2-3/dayWith cold, usually rareDaily to yearly