**Core Concept**
The composition of soda lime is a critical factor in the proper functioning of CO2 absorbent systems used in anesthesia machines. The mixture of sodium hydroxide (NaOH), calcium hydroxide (Ca(OH)2), and potassium hydroxide (KOH) is essential for the efficient absorption of carbon dioxide from anesthetic gases.

**Why the Correct Answer is Right**
The correct composition of soda lime is crucial for its effectiveness in CO2 absorption. Sodium hydroxide (NaOH) is the primary CO2 absorbent, reacting with CO2 to form sodium carbonate (Na2CO3). Calcium hydroxide (Ca(OH)2) acts as a desiccant, helping to maintain a dry environment within the CO2 absorbent canister. Potassium hydroxide (KOH) is added to maintain the stability of the mixture and prevent the degradation of the absorbent. The precise ratio of these components is essential to ensure the efficient removal of CO2 and maintain the quality of the anesthetic gases.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not list the correct components of soda lime.
* **Option B:** This option is incorrect because it does not specify the correct ratio of NaOH to Ca(OH)2 to KOH.
* **Option C:** This option is incorrect because it does not include potassium hydroxide (KOH), which is a critical component of the mixture.

**Clinical Pearl / High-Yield Fact**
The composition of soda lime can be remembered using the mnemonic "Sodium, Calcium, Potassium" (SCP), with each letter corresponding to the first letter of each component.

**Correct Answer: D. NaOH Ca(OH)2 KOH**