The process of release of urine is called micturition and the neural mechanisms causing it is called the micturition reflex.

(i) Urine formed by the nephrons is ultimately carried to the urinary bladder/

(ii) This signal is initiated by the stretching of the urinary bladder as it gets filled with urine.

(iii) In response, the stretch receptors on the walls of the bladder send signals to the CNS.

(iv) The CNS passes motor messages to initiate the contraction of smooth muscles of the bladder causing the release of urine.

Choose correct option which contain correct order of phenomena of micturition: