Okay, let's tackle this question about Knutson's technique. First, I need to recall what Knutson's technique refers to. I remember that in ophthalmology, there are various surgical techniques for procedures like cataract surgery or corneal transplants. Wait, Knutson's technique is related to a specific type of corneal graft, maybe a lamellar keratoplasty? Or perhaps it's a technique for creating a corneal flap?

Wait, lamellar keratoplasty involves replacing only a portion of the cornea. There are different types like DALK (Deep Anterior Lamellar Keratoplasty) and DSEK (Descemet's Stripping Endothelial Keratoplasty). Knutson's technique might be a specific method within one of these. Let me think. The Knutson technique is used in Descemet's stripping automated endothelial keratoplasty (DSAEK) or DMEK. It's a method for preparing the donor tissue by creating a thin sheet of Descemet's membrane and endothelium.

So the options might be about the layers or tools used. The core concept here is the preparation of donor tissue for endothelial keratoplasty. The correct answer would be the specific step or instrument used in Knutson's technique. For example, using a microkeratome or a specific cutting blade to create the thin graft.

Now, the wrong options could include other techniques like using a femtosecond laser, which is used in DSEK but not specifically Knutson's. Or maybe using a different type of keratoplasty like DALK. Another distractor might be a technique for creating a flap in LASIK, which is unrelated to corneal transplants.

So the correct answer is likely related to the method of preparing the Descemet's membrane and endothelium. Let me verify. Knutson's technique involves using a microkeratome to create a posterior lamellar graft, which is then stripped to leave Descemet's membrane and endothelium. Therefore, the correct answer would be the use of a microkeratome. The other options would be incorrect because they refer to different techniques or tools used in other procedures.

I need to structure the explanation with the core concept first, explaining that Knutson's technique is a method for preparing donor tissue in endothelial keratoplasty. Then explain why the correct answer is right by detailing the use of the microkeratome. Then address each wrong option, explaining why they are incorrect. Finally, the clinical pearl would highlight that Knutson's technique is a key method for DSAEK/DSAEK. The correct answer is the one that mentions the microkeratome.

**Core Concept**
Knutson's technique is a method used in **Descemet's stripping endothelial keratoplasty (DSEK/DSAEK)** to prepare a thin posterior corneal graft. It involves creating a posterior lamellar graft composed of Descemet’s membrane and endothelium using a **microkeratome** or manual dissection. This technique is critical for treating corneal endothelial dysfunction.

**Why the Correct Answer is Right**
The correct answer describes the use of a **microkeratome** to create a posterior lamellar graft. Knutson's technique involves slicing

✓ Correct Answer: C. 2% Na Fluoride