Each of the following questions is based on the following alphabet series.
A B C D E F G H I J K L M
N O P Q R S T U V W X Y Z
If every even letter beginning from B is replaced by odd number starting with 3, which letter/ number will be the third to the right of the tenth number/letter counting from your right.

Options

A. M
B. S
C. 11
D. 21

Explanation

To solve the problem step by step, we will follow the instructions given in the question.

### Step 1: Understand the Alphabet Series
The alphabet series provided is:
```
A B C D E F G H I J K L M
N O P Q R S T U V W X Y Z
```

### Step 2: Identify Even Letters Starting from B
We need to replace every even-positioned letter starting from B with odd numbers starting from 3. The even-positioned letters in the series are:
- B (2nd position)
- D (4th position)
- F (6th position)
- H (8th position)
- J (10th position)
- L (12th position)
- N (14th position)
- P (16th position)
- R (18th position)
- T (20th position)
- V (22nd position)
- X (24th position)
- Z (26th position)

### Step 3: Replace Even Letters with Odd Numbers
We will replace these even letters with odd numbers starting from 3:
- A (1st position) remains A
- B (2nd position) becomes 3
- C (3rd position) remains C
- D (4th position) becomes 5
- E (5th position) remains E
- F (6th position) becomes 7
- G (7th position) remains G
- H (8th position) becomes 9
- I (9th position) remains I
- J (10th position) becomes 11
- K (11th position) remains K
- L (12th position) becomes 13
- M (13th position) remains M
- N (14th position) becomes 15
- O (15th position) remains O
- P (16th position) becomes 17
- Q (17th position) remains Q
- R (18th position) becomes 19
- S (19th position) remains S
- T (20th position) becomes 21
- U (21st position) remains U
- V (22nd position) becomes 23
- W (23rd position) remains W
- X (24th position) becomes 25
- Y (25th position) remains Y
- Z (26th position) becomes 27

### Step 4: Write the New Series
After replacing, the new series looks like this:
```
A 3 C 5 E 7 G 9 I 11 K 13 M 15 O 17 Q 19 S 21 U 23 W 25 Y 27
```

### Step 5: Find the Tenth Number/Letter from the Right
Now, we need to find the 10th number/letter counting from the right:
1. Y (1st)
2. 25 (2nd)
3. W (3rd)
4. 23 (4th)
5. U (5th)
6. 21 (6th)
7. S (7th)
8. 19 (8th)
9. Q (9th)
10. 17 (10th)

So, the 10th number/letter from the right is **17**.

### Step 6: Find the Third to the Right of 17
Now we need to find the letter/number that is third to the right of 17:
1. 19 (1st right)
2. S (2nd right)
3. 21 (3rd right)

Thus, the letter/number that is third to the right of 17 is **21**.

### Final Answer
The answer to the question is **21**.

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