In recent years, there has been some concern over the threat posed by the Mathura Oil Refinery and the thermal power plants to the Taj Mahal in Agra. The scientific basis of any possible damage to the Taj is mainly

(a)

stratospheric ozone and the chlorofluorocarbons which destroy it

(b)

acid precipitation and tropospheric ozone

(c)

increasing levels of atmospheric CO2 which produce the greenhouse effect

(d)

ultraviolet radiation (240-260 nanometers wavelength) and the fumes from the heavily polluted Yamuna river