The question is stated wrong.It should be: "What is the next letter in the series O T T F F ?", and the answer is " S ".These are the initial letters of the words: One Two Three Four Five, followed by Six.
d
It looks as if every third letter is an "r"; the remaining letters are in sequence.
E. They are the initial letters of the numbers 0-7 in words: Zero, One, Two, Seven The next is 8 - Eight
oNe, tWo, tHree, fOur,fIve,sIx etc. It is the second letter of each consecutive number
This looks like two series interspered with each other. Let's put some letters in upper-case and others in lower-case BaCbDcEdF... so the next letter would be the lower-case 'e'
The series CYGTNLIT appears to be a simple pattern where each letter is the next letter in the alphabet from the previous letter. Therefore, the next letter in the series would be M.
what is the next letter e h l q
X
c
Q
The next (and last) letter is C. Just as a countdown counts backwards, this series is "countdown" spelled backwards.
c is next
y
S
T
It's the letter D of course! Haven't you heard of Jason D?!