When Curiosity Mars rover, having been launched in November 2011 and landing on Mars in the Aeolis Palus plain in August 2012, scientists discovered that a 2.5 meter wide rock contained traces of elements hinting towards existence of water on the Martian surface sometime in the past and that the Martian surface has been hit by ten times as many meteors as the earth’s surface has been.

A.When Curiosity Mars rover, having been launched in November 2011 and landing on Mars in the Aeolis Palus plain in August 2012, scientists discovered that a 2.5 meter wide rock contained traces of elements hinting towards:
DC STARTING WITH 'WHEN' DON'T HAVE A VERB

B.In August 2012, when Curiosity Mars rover launched in November 2011 landed on Mars in the Aeolis Palus plain, scientists discovered that a 2.5 meter wide rock containing traces of elements hinting towards:
CLAUSE STARTING WITH 'A 2.5 METER' DON'T HAVE A VERB.

C.Curiosity Mars rover, having launched in November 2011 and landed on Mars in the Aeolis Palus plain in August 2012, scientists discovered that a 2.5 meter wide rock containing traces of elements that hinted towards:
CLAUSE STARTING WITH 'CURIOSITY MARS ROVER' DON'T​HAVE A VERB.

D.When Curiosity Mars rover, launched in November 2011, landed on Mars in the Aeolis Palus plain in August 2012, scientists discovered that a 2.5 meter wide rock contained traces of elements that hinted towards:
CORRECT

E.Discovering a 2.5 meter wide rock containing traces of elements, Curiosity Mars rover that was launched in November 2011 and that landed on Mars in the Aeolis Palus plain in August 2012, scientists hinted towards:
SAME ERROR AS C

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