**Core Concept**
Prostatism refers to a set of urinary symptoms in men, often associated with benign prostatic hyperplasia (BPH) or prostatic cancer. The assessment of a patient with prostatism involves a comprehensive evaluation to differentiate between these conditions and identify any underlying complications.

**Why the Correct Answer is Right**
A thorough assessment of prostatism includes a detailed history, physical examination, and diagnostic tests to evaluate urinary symptoms, prostate size, and potential complications such as urinary retention or bladder stones. This evaluation may involve digital rectal examination (DRE), uroflowmetry, and imaging studies like ultrasound or MRI to assess prostate size and any potential obstructions. Additionally, laboratory tests such as PSA (prostate-specific antigen) levels and urinalysis may be performed to rule out underlying conditions like infection or malignancy.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it is not commonly used in the assessment of prostatism. While it may be used to evaluate some urinary symptoms, it is not a primary tool for assessing prostatism.

**Option B:** This option is incorrect as it is not a direct assessment tool for prostatism. While it may be used to evaluate some symptoms, it is not a specific or sensitive test for prostatism.

**Option C:** This option is incorrect as it is not a primary diagnostic tool for prostatism. While it may be used to evaluate some urinary symptoms, it is not a specific or sensitive test for prostatism.

**Clinical Pearl / High-Yield Fact**
A key aspect of assessing prostatism is to differentiate between BPH and prostatic cancer. A PSA level above 4 ng/mL in men over 50 years old warrants further investigation, including imaging studies and biopsy.

**Correct Answer: D.**