$A$ well-developed Loop of Henle is found in:

Identify the correct statements:
$I.$ The outer layer of the kidney is called a capsule.
$II.$ The kidney is divided into an outer cortex and an inner medulla.
$III.$ The medulla is divided into medullary pyramids.
$IV.$ The cortex extends in between the medullary pyramids,which is called the columns of Bertini.
Choose the correct option accordingly.

Identify the wrong statements about the human excretory system and choose the option accordingly.
$I.$ Kidneys are reddish-brown and bean-shaped structures.
$II.$ Kidneys are situated between the last thoracic and third lumbar vertebrae.
$III.$ Each kidney of an adult human measures $10-12 \, cm$ in length,$5-7 \, cm$ in width,$2-3 \, cm$ in thickness,and has an average weight of $120-170 \, g$.

The following figure shows a longitudinal section of the kidney. Which part represents the renal column?

The renal columns of Bertin are extensions of the ...... into the renal medulla.

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: Nephrons are of two types: Cortical and Juxta-medullary,based on their relative position in the cortex and medulla.
Reason $R$: Juxta-medullary nephrons have a short loop of Henle,whereas cortical nephrons have a longer loop of Henle.
In the light of the above statements,choose the correct answer from the options given below: