Find the last five missing letters of the series :
a – aabb– –ab – b – – – –

Options

A. baaaa
B. babab
C. baaba
D. bbaaa

Explanation

To find the last five missing letters of the series: a – aabb – – ab – b – – – – , we can analyze the pattern in the given letters.

1. **Identify the given letters**: The series provided is:
- a
- aabb
- ab
- b
- (missing)
- (missing)
- (missing)
- (missing)
- (missing)

2. **Look for a pattern**: Let's break down the series:
- The first letter is "a".
- The second part is "aabb", which consists of two 'a's and two 'b's.
- The third part is "ab", which consists of one 'a' and one 'b'.
- The fourth part is "b", which consists of one 'b'.

3. **Analyze the sequence**:
- The first part has one 'a'.
- The second part has two 'a's and two 'b's.
- The third part has one 'a' and one 'b'.
- The fourth part has one 'b'.

4. **Determine the missing parts**:
- It seems like the sequence is alternating between 'a's and 'b's, and the number of letters is decreasing:
- 1 'a' → 2 'a's and 2 'b's → 1 'a' and 1 'b' → 1 'b'.
- Following this pattern, the next parts should continue with 'a's and 'b's.

5. **Fill in the missing letters**:
- The fifth part could be "a" (following the pattern of alternating).
- The sixth part could be "aa" (adding one more 'a').
- The seventh part could be "b" (following the pattern).
- The eighth part could be "bb" (adding one more 'b').
- The ninth part could be "a" (returning to 'a').

Thus, the last five missing letters are: a, aa, b, bb, a.

Final series: a, aabb, ab, b, a, aa, b, bb, a.