Select the option that represents the letters that, when sequentially placed from left to right in the blanks below, will complete the letter series.
p _ r _ p o _ p o r b _ o _ p o r b _ o r
1
o b p p o p
2
o b o p r p
3
o b r p r o
4
o b r p r p
Select the option that represents the letters that, when sequentially placed from left to right in the blanks below, will complete the letter series.
p _ r _ p o _ p o r b _ o _ p o r b _ o r