$A$ kind of similarity found in polar regions and high altitudes is

Define phenotypic adaptation. Give one example.

Factors which determine to the large extent the vegetation of any area are

$I.$ $pH$ of soil

$II.$ mineral composition of the soil

$III.$ water holding capacity of soil

$IV.$ weather condition

Choose the correct option

Which of the following is a climatic factor

Assertion $(A):$ A person goes to high altitude and experiences 'altitude sickness' with symptoms like breathing difficulty and heart palpitations.

Reason $(R):$ Due to low atmospheric pressure at high altitude, the body does not get sufficient oxygen.

In the light of the above statements, choose the correct answer from the options given below.