Consider the given statements and select the option that correctly states them as true (T) or false (F).
A. Long exposure to harmful substances, gases, fumes and dust produced in certain industries can give rise to inflammation in lungs leading to fibrosis.
B. When percentage saturation of haemoglobin with O2 is plotted against pO2, the curve obtained is described as hyperbola.
C. Presence of low levels of HCO−3 ions and high levels of O2 can activate the chemosensitive area present adjacent to rhythm centre.
D. Skin is not a respiratory organ in humans.