<prompt> A patient gets reccurent urticaria while doing exercise and on exposure to sunligh. Which of the following is most like causeChronic Idiopathic UtricariaUniversal dermographismCholinergic utricariaphotodermatitis  <response>: This patient develops urticaria after:-ExerciseExposure to sunlight generalized heatingBoth of these provoke cholinergic urticaria due to stimulation of cholinergic sympathetic fibres. 