  In this letter, the old issue of whether redshifts of quasars are of
cosmological origin is investigated. We make a plot of absorption redshifts
versus emission redshifts for quasars with large amounts of data. Our study
shows that, almost all absorption redshifts are smaller than the corresponding
emission redshifts. The relation between the absorption and emission redshifts
predicted by current cosmological models is well obeyed. The result confirms
that redshifts of quasars are indeed distance indicators. It might be the most
obvious evidence found so far to be consistent with the cosmological
interpretation of quasar redshifts.
