Correct Option (3)
The given sequence is A_BCD_BBCDABC_DABC_D. Upon careful observation, the sequence can be segmented into four distinct blocks, each following a specific progressive pattern:
- The first block is AABCD. This implies the first blank is filled by 'A'.
- The second block is ABBCD. This implies the second blank is filled by 'A'.
- The third block is ABCCD. This implies the third blank is filled by 'C'.
- The fourth block is ABCDD. This implies the fourth blank is filled by 'D'.
Therefore, the complete sequence becomes AABCDABBCDABCCDABCDD, and the missing letters are A, A, C, D.
Incorrect Options:
Options 1, 2, and 4 do not adhere to the identified progressive pattern of AABCD, ABBCD, ABCCD, ABCDD. Substituting the letters provided in these options into the blanks would disrupt the logical progression and consistency of the series.