**Core Concept**
The underlying condition described in the question is a type of urinary incontinence characterized by involuntary loss of urine during activities that increase abdominal pressure. This condition is often associated with weakened pelvic floor muscles, particularly the urethral sphincter.

**Why the Correct Answer is Right**
The symptoms described in the question are classic for stress urinary incontinence (SUI). SUI occurs when increased abdominal pressure, such as during coughing, laughing, lifting, or standing, exceeds the urethral closure pressure, leading to involuntary urine leakage. This is often due to weakened pelvic floor muscles, particularly the urethral sphincter, which fails to maintain adequate urethral closure pressure.

**Why Each Wrong Option is Incorrect**
* **Option A:** Urge incontinence is characterized by involuntary loss of urine associated with a sudden, strong urge to urinate, not with activities that increase abdominal pressure.
* **Option B:** Overflow incontinence is characterized by a constant, slow leakage of urine due to an overfilled bladder, not with activities that increase abdominal pressure.
* **Option C:** Functional incontinence is characterized by a physical inability to reach the toilet in time, often due to cognitive impairment or mobility issues, not with involuntary loss of urine due to increased abdominal pressure.

**Clinical Pearl / High-Yield Fact**
Stress urinary incontinence is often associated with pelvic organ prolapse, which can worsen symptoms and reduce quality of life. Patients with SUI should be evaluated for pelvic organ prolapse and considered for pelvic floor physical therapy or surgical intervention if necessary.

**Correct Answer:** C. Stress Urinary Incontinence