Complete the following sentence by selectrin the correct option.
Receptors associtated with aortic arch and carotid artery can recognise changes in `overset((i))"______"` and `overset((ii))"______"` concentration and send necessary signals to `overset((iii))"______"` for remedial actions.

Options

A. `{:("(i)",(ii),(iii)),(O_(2),CO_(2),"pneumotaxic centre"):}`
B. `{:("(i)",(ii),(iii)),(CO_(2),H^(+),"rhythm centre"):}`
C. `{:("(i)",(ii),(iii)),(CO_(2),H^(+),"apneustic centre"):}`
D. `{:("(i)",(ii),(iii)),(O_(2),H^(+),"pneumotaxic centre"):}`

Explanation

To complete the sentence, we need to identify the correct options for the blanks in the statement. The sentence is:

"Receptors associated with aortic arch and carotid artery can recognise changes in `overset((i))"______"` and `overset((ii))"______"` concentration and send necessary signals to `overset((iii))"______"` for remedial actions."

### Step-by-Step Solution:

1. **Identify the first blank (i)**:
- The receptors in the aortic arch and carotid artery primarily monitor the levels of carbon dioxide (CO2) in the blood. Therefore, the correct option for the first blank is **"CO2"**.

2. **Identify the second blank (ii)**:
- In addition to CO2, these receptors also detect changes in hydrogen ion concentration (H+), which is related to the acidity of the blood. Thus, the correct option for the second blank is **"H+"**.

3. **Identify the third blank (iii)**:
- The signals from these receptors are sent to the respiratory rhythm center, which is located in the medulla oblongata of the brain. Therefore, the correct option for the third blank is **"medulla"** or **"respiratory rhythm center"**.

### Final Completed Sentence:
"Receptors associated with aortic arch and carotid artery can recognise changes in `overset((i))"CO2"` and `overset((ii))"H+"` concentration and send necessary signals to `overset((iii))"medulla"` for remedial actions."