Human body compensates low oxygen availability at high altitudes by:

(A) increasing number of red blood cells
(B) decreasing the binding affinity of haemoglobin
(C) increasing the binding affinity of haemoglobin
(D) increasing breathing rate

Choose the correct answer from the options given below:

(A), (B) and (D) only

The correct answer is Option (3) → (A), (B) and (D) only