Answer:
The urinary bladder is best described as an elastic sac of muscles that holds urine until it is voided (option B).
Step-by-step explanation:
The urinary bladder is the organ of the urinary system that receives urine from the kidneys and stores it until it is expelled through the urethra. It is a hollow organ whose muscular structure is elastic, allowing it a certain range of stretching in order to contain liquids.
Apart from the muscular layer, the urinary bladder has an inner layer, or mucosa, and a serous surface layer.
The other options are not correct because the urinary bladder:
A. It is not a tube that connects the kidney to the renal pelvis.
C. It is not a tube that connects to the blood vessels.
D. It is present in humans.