**Core Concept**
LASIK (Laser-Assisted In Situ Keratomileusis) surgery is a refractive surgical procedure used to correct vision problems such as myopia, hyperopia, and astigmatism. The suitability of a patient for LASIK surgery depends on several factors, including the severity of their refractive error, the stability of their refraction, and the thickness of their cornea.

**Why the Correct Answer is Right**
Option B, "Age of 15 years", is incorrect because LASIK surgery is typically not recommended for individuals under the age of 18. This is because the eyes of adolescents, particularly those under the age of 18, are still developing, and their refractive errors may change over time. In fact, the American Academy of Ophthalmology recommends that LASIK surgery be performed on patients who are at least 18 years old, and ideally in their mid-to-late 20s when their refractive errors have stabilized. This allows for more accurate predictions of post-operative outcomes and reduces the risk of complications.

**Why Each Wrong Option is Incorrect**
**Option A:** A myopia of 4 diopters is generally considered suitable for LASIK surgery, as it is within the range that can be effectively corrected with this procedure.

**Option C:** A stable refraction for 1 year is a desirable criterion for LASIK surgery, as it indicates that the patient's refractive error has been stable and is unlikely to change significantly in the near future.

**Option D:** A corneal thickness of 600 microns is generally considered adequate for LASIK surgery, as it provides sufficient tissue for the creation of a flap and the removal of the underlying tissue.

**Clinical Pearl / High-Yield Fact**
It's essential to note that patients with a history of keratoconus, corneal dystrophies, or other corneal abnormalities may not be suitable candidates for LASIK surgery.

**✓ Correct Answer: B. Age of 15 years.**