c c cbb - aa - c c - bbbaa -

Options

A. acbc
B. baca
C. baba
D. acba

Explanation

To solve the series completion question, we need to identify the pattern in the given sequences and determine which option fits best in the middle. The sequences provided are:

1. CCCBB
2. AA
3. CC
4. BBBAA

Let's analyze the sequences step by step:

### Step 1: Identify the Pattern
We need to observe the sequences to find a recurring pattern. The sequences consist of letters 'C', 'B', and 'A'.

- The first sequence is **CCCBB**: This has 3 'C's followed by 2 'B's.
- The second sequence is **AA**: This has 2 'A's.
- The third sequence is **CC**: This has 2 'C's.
- The fourth sequence is **BBBAA**: This has 3 'B's followed by 2 'A's.

### Step 2: Look for Consistency
Now, let's look for a consistent structure. We can see that:
- The first sequence has 3 'C's and 2 'B's.
- The second sequence has 2 'A's.
- The third sequence has 2 'C's.
- The fourth sequence has 3 'B's and 2 'A's.

### Step 3: Formulate the Next Sequence
To find the missing sequence, we can hypothesize that the next sequence should continue the pattern established by the previous sequences.

Given the sequences, we can observe:
- The pattern seems to alternate between groups of 'C's, 'B's, and 'A's.
- The number of letters in each group seems to be decreasing or changing systematically.

### Step 4: Test the Options
Now, we need to test the provided options to see which one fits best in the sequence. The option given is **BA-CA-BAACAA**.

If we insert this option into the sequence, we would have:
- CCCBB
- AA
- BA-CA-BAACAA
- CC
- BBBAA

Now, let's analyze if this fits:
- The inserted sequence contains 'B's and 'A's, which aligns with the previous sequences.
- The structure of 'BA-CA-BAACAA' seems to introduce a new pattern that complements the existing sequences.

### Conclusion
After analyzing the sequences and testing the options, we find that inserting **BA-CA-BAACAA** maintains the overall structure and pattern of the series. Therefore, the correct answer is option B.