Pulmonary Hypertension is defined as Pulmonary Artery Pressure-

Ans. is 'd' i.e., > 25 mmHg (Link; Documenis/guidelines-PH-FTpdf)o PH has been defined as an increase in mean pulmonary arterial pressure (PAP) > 25 mmHg at rest as assessed by right heart catheterization (RHC').DefinitionCharacteristicsClinical group(s)Pulmonary- hypertension (PH)o Mean PAP > 25mmHgo AllPre-capillary PHo Mean PAP > 25mmHgo PWP < ISmmHgo CO normal or reducedo Pulmonary arterial hypertensiono PH due to lung diseaseso Chronic thromboembolic PHo PH with under andfar multifactorial mechanismsPost-capillary PHo Mean PAP > ISmmHgo PWP >ISmmHgo CO normal or reducedo PH due to left heart diseaseNote; High CO can be present in cases of hyperkinetic conditions such as systemic to-pulmonarv shunts (only in the pulmonary circulation). Anaemia, Hyperthyroidism, etc.CO = cardiac output; PAP = pulmonary arterial pressure; PH = pulmonary hypertension; PWP = pulmonary wedge pressure.