often = most?? CR question

[rte.sushil]

This question has freaked me out but on analysing to depth i reached at a general verbal query, which is given below following the question.
Those who want to solve, here is the questioon:-

Mystery stories often feature a brilliant detective and the detective’s dull companion. Clues are presented in the story, and the companion wrongly infers an inaccurate solution to the mystery using the same clues that the detective uses to deduce the correct solution. Thus, the author’s strategy of including the dull companion gives readers a chance to solve the mystery while also diverting them from the correct solution.
Which one of the following is most strongly supported by the information above?
(A) Most mystery stories feature a brilliant detective who solves the mystery presented in the story.
(B) Mystery readers often solve the mystery in a story simply by spotting the mistakes in the reasoning of the detective’s dull companion in that story.
(C) Some mystery stories give readers enough clues to infer the correct solution to the mystery.
(D) The actions of the brilliant detective in a mystery story rarely divert readers from the actions of the detective’s dull companion.
(E) The detective’s dull companion in a mystery story generally uncovers the misleading clues that divert readers from the mystery’s correct solution.

Answer: C

My Query:
I selected A
it is given in the answer choices: Most mystery stories
but the stimulus has given: Mystery stories often feature a brilliant detective

When i analysed these 2 statements, i found them similar because
From the argument statement, mystery often features means they usually have detectives. So if we have 100 of mystery stories, detectives will be usually present, therby meaning more than 50%.
From A: Most mystery stories feature a brilliant detective. It is straighforward that more than 50% will have mystery stories.

often means almost regularly, happening frequently, right? then why am i wrong:(

[Willy]

No, I don't think we can say MOST = OFTEN.

As you have noted 'Often' means frequently, regularly. Now, suppose there are 100 mystery stories and detectives appear in 1st, 10th, 20th, 30th,......, and 90th mystery story. What we will say about this? Ans. - Detectives appear frequently or detectives appear regularly, no matter detectives appear only in 10 stories, we'll say 'Often' - regularly.

'Most' means more than half.

[jlucero]

Willy is correct. The grammatical difference is that most is an adj and often is an adv. That's why they are not interchangeable. And the meaning difference obviously is important here too.

I like most (what kinds of music) music.
I often (when do I like) like music.