GMAT Sentence Correction
Ozone, a special form of oxygen that screens out harmful ultraviolet rays, reaches high concentrations twelve miles above Earth, where it has long appeared that it was immune from human influence; we have now realized, though, that emissions of industrial chlorofluorocarbons deplete the ozone layer.
- A has long appeared that it was immune from
- B has long appeared to have been immune from
- C has long appeared as being immune to
- D had long appeared immune to
- E had long appeared that it was immune to
Correct Answer: D