**Core Concept**
Stone formation in alkaline urine is a well-known phenomenon in urology, primarily due to the precipitation of calcium salts. The pH-dependent solubility of certain minerals, such as calcium oxalate, plays a crucial role in stone formation. In alkaline urine, the increased concentration of calcium ions can lead to the formation of calcium phosphate stones.

**Why the Correct Answer is Right**
In alkaline urine, the pH-dependent solubility of calcium salts is altered, leading to an increased risk of stone formation. Calcium phosphate stones, in particular, are more likely to form in alkaline environments due to the precipitation of calcium phosphate crystals. This process is facilitated by the presence of magnesium and phosphate ions, which can act as precipitants. Furthermore, the increased pH in alkaline urine can also lead to the formation of calcium oxalate stones, although this is less common.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not relevant to the question, as it does not address the relationship between urine pH and stone formation.
**Option B:** This option is incorrect because struvite stones are more commonly associated with urinary tract infections, particularly those caused by urease-producing bacteria, rather than alkaline urine pH.
**Option C:** This option is incorrect because uric acid stones are more commonly associated with acidic urine pH, rather than alkaline urine pH.

**Clinical Pearl / High-Yield Fact**
A key clinical correlation to remember is that patients with recurring kidney stones should be evaluated for underlying metabolic disorders, such as hyperparathyroidism or renal tubular acidosis, which can contribute to alkaline urine pH and stone formation.

**Correct Answer: D. Calcium phosphate stones**