Although an initial analysis of the rock samples
that had been gathered by the Mars Pathfinder mission, revealing traces of water on the Martian surface and generating excited debate about the possibility of life on the planet, more recent evaluations have cast doubt on those speculations, suggesting that the Martian environment is too hostile to sustain life.
A. that had been gathered by the Mars Pathfinder mission, revealing traces of water on the Martian surface and generating excited debate about the possibility of life on the planet, more recent evaluations have cast doubt on those speculations, suggesting
B. gathered by the Mars Pathfinder mission revealed traces of water on the Martian surface and generated excited debate about the possibility of life on the planet, but more recent evaluations have cast doubt on those speculations and have suggested
C. gathered by the Mars Pathfinder mission revealed traces of water on the Martian surface, generating excited debate about the possibility of life on the planet, more recent evaluations have cast doubt on those speculations, suggesting
D. that had been gathered by the Mars Pathfinder mission has revealed traces of water on the Martian surface and generated excited debate about the possibility of life on the planet, more recent evaluations have cast doubt on those speculations and suggested
E. gathered by the Mars Pathfinder mission has revealed traces of water on the Martian surface, generating excited debate about the possibility of life on the planet, but more recent evaluations have cast doubt on those speculations and have suggested