Correct Answer - Option 4 : 56
EXPLANATION:
The logic applied: odd place numbers are getting double and even digit numbers are getting triple in value. So, we have to find out the 7th number of the series.
So to find that out we have to double the number which is in the 5th position. The number in the 5th position is 28 and double of 28 is 56 so our answer is 56.