Question Detail

Original: CGATTACCATGCATA. Mutant 1: CGATTAACCTGCATA. Compare: After 'CGATTA', original has 'C', mutant 1 has 'AAC'. It looks like an extra 'A' was inserted ('C' -> 'AAC'), and then the rest of the sequence is shifted. This is an insertion. Mutant 2: CGATTACCAGGCATA. Compare to original: where original had 'T' (in 'ATGC'), mutant 2 has 'G' (in 'AGGC'). This appears to be a single base change, a substitution. However, looking closer at Mutant 1, it seems an 'A' was inserted, but the original 'C' might be lost? Actually, Original: ...TAC CAT G... (TAC, then C). Mutant1: ...TAA CCT G... The 'C' from the original is present? This is tricky. Let's align properly. Original: CGAT TAC CAT GCA TA. Mutant1: CGAT TAA CCT GCA TA. So 'C' (position 6) is replaced by 'A', and a 'C' is inserted? This is more complex. Given the options, and common question patterns, Mutant 1 is often a frameshift from an insertion, and Mutant 2 is a substitution. Option B is insertion and deletion. Option D is substitution and insertion. Since Mutant 2 looks like a substitution, D is a better fit. Let's re-examine Mutant 2: Original: ...CAT GCA... Mutant2: ...CAG GCA... The 'T' changed to 'G'. Yes, that's a substitution. So Mutant 1 is an insertion. The correct answer based on this analysis is D: substitution and insertion. However, the options list 'substitution and insertion' as D. I will go with D.