Explanation:

Correct Answer is (d).I. The Gujarat election, which was expected to be an easy win for the BJP, has unexpectedly developed into a possibly close and certainly engrossing contest.
This is correct both contextually and grammatically.
II. The Gujarat election, which was expected to be an easy win for the BJP, seems to have infused new life into Congress vice-president Rahul Gandhi’s floundering political career just weeks before his likely elevation as the party president.
This is correct both contextually and grammatically.
III. The Gujarat election, which was expected to be an easy win for the BJP, has gone all out since then to broadcast and publicise the social media campaign captured by the image of an upturned state transport bus with its wheels off.
This is incorrect. From the sentence structure, It looks like Gujarat itself has gone all out which does not make sense.
Hence, option D is correct.