In which of the following is the minimum content of urea present?

Renal pyramids are parts of the ...... .

The figure shows the human urinary system with structures labelled $A$ to $D$. Select the option which correctly identifies them and gives their characteristics and/or functions.

Complete the analogy.
$Renal \text{ } pelvis : \text{ } ureter :: \text{ } Renal \text{ } cortex : \text{ } . . . . . . $

Given below are two statements:
Statement $I$: At the base of the urinary bladder,there is an inverted triangular area called the trigone.
Statement $II$: Three layers of dartos tunic muscles are present in the wall of the urinary bladder.
In the light of the above two statements,choose the correct option.

Henle's loops are found in those animals which excrete hypertonic urine. One of the following does not have Henle's loop.