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					 Which one set of letters when sequentially placed at the gaps in the given letter series shall complete it?
 _ ab _ b _ bc _ ca _
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                        - accbb
- abcca
- cacab
- abacb
 
Correct Option: C
The given letter series in below pattern.
c ab/ a b c
After completing the pattern, we will get complete letter series.
c ab/ a b c/ bc a/ ca b
 
	