Correct answer-
a. lower folds of the urinary bladder- This is the correct answer because the bladder is the only part of the urinary tract which is home to microflora or microorganisms, even if the individual is healthy. This region is not sterile.
Incorrect answers-
b. nephrons- This is incorrect because the nephrons are involved in the process of urine filtration from blood. This region needs to be sterile so that filtration can be carried out without contamination.
c. the ureter of the kidney- This is incorrect because the ureter is sterile because of the chemical composition of the urine that travels through it to the bladder.
d. the portion of the urethra closest to the urethral opening- This is also incorrect because if the urethra or urethral opening is not sterile this leads to urinary tract infection or UTI.
Lear more about urinary tract here-
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