Number of letters skipped in between adjacent letters in the series decrease by one. Which of the following series is observing the rule?

Choose the series in which the number of letter skipped in between adjacent letters is decreasing by one.

Choose the series in which the number of letter skipped in between adjacent letters is decreasing by two.

Choose the series in which the number of letters skipped in between adjacent letters is 2, 5, 7 and 10 respectively.

Choose the series in which the number of letters skipped in between adjacent letters is always 2.

Choose the series in which the number of letters skipped in between adjacent letters is always same.

Choose the series in which the number of letters skipped in between adjacent letters is increasing by one.

Choose the series in which the number of letters skipped in between adjacent letters is increasing by one.

Choose the series in which the number of the letters skipped in between adjacent letters is increasing by one.

Choose the series in which the number of the letters skipped in between adjacent letters is increasing by one.