Earliest radiological sign of pulmonary venous hypertension in chest X-ray is –

Cephalization of pulmonary vascularity is the first radiological sign of pulmonary venous hypertension amongst the options provided. Pulmonary venous hypertension results in diversion of blood flow from lung bases to the zipper lobes. This reversal of normal gravity dependent pattern and upper lobe venous diversion is first radiological sign.