<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 75-year-old man presents to the physician because of bloody urine, which has occurred several times over the past month. He has no dysuria or flank pain. He has no history of serious illness, and he currently takes no medications. He is a 40-pack-year smoker. The vital signs are within normal limits. Physical exam shows no abnormalities except generalized lung wheezing. The laboratory test results are as follows:Urine:Blood 3RBC 100hpfWBC 12hpfRBC casts negativeBacteria not seenCystoscopy reveals a solitary tumor in the bladder. Transurethral resection of the bladder tumor is performed. The tumor is 4 cm. Histologic evaluation shows invasion of the immediate epithelium of cells by a high-grade urothelial carcinoma without invasion of the underlying tissue or muscularis propria. Which of the following is the most appropriate next step in management?? A: Bladder radiation, B: Bladder-sparing partial cystectomy, C: Intravesical Bacille Calmette-Guérin BCG, D: Systemic combination chemotherapy, E: No further treatment is needed at this time,  <response>: This is a question about the management of a patient with a high-grade, non-invasive bladder cancer. Key points from the stem:- 75 year old man with hematuria and solitary bladder tumor on cystoscopy - Tumor is 4 cm in size- Histology shows high-grade urothelial carcinoma without muscle invasion- No metastases are mentionedFor a high-grade, non-invasive stage Ta bladder cancer, the options are:A Bladder radiation - not recommended as first-line for this stage B Bladder-sparing partial cystectomy - too aggressive for non-invasive tumorC Intravesical BCG - correct option; BCG is first-line adjuvant therapy after resection of high-grade non-invasive bladder cancerD Systemic chemotherapy - not indicated for non-invasive diseaseE No further treatment - incorrect since high-grade tumors have high risk of recurrence and progressionC: Intravesical Bacille Calmette-Guérin BCG 