In alphabet series, some alphabets are missing which are given in that order as one of the alternatives below it. Choose the correct alternative.
a _ bc _ a _ bcda _ ccd _ bcd _
a _ ca _ bc _ bcc _ bca
cab _ a _ c _ bc _ bc _ b _ ab
a _ c _ abb _ a _ bc _ bc _ ab
_ _ babbba _ a _ _
ccbab _ caa _ bccc _ a _