Consider the following statements about haemoglobin:

1. It contains iron
2. It is a carrier of oxygen in the blood.
3. It imparts red colour to the blood.
4. It provides immunity against certain diseases.

Of these statements:

A) 1, 2 and 4 are correct

B) 1, 2 and 3 are correct

C) 2, 3 and 4 are correct

D) 1, 3 and 4 are correct

This MCQ is part of the UP PSC Previous Year Questions (PYQs) series, focusing on UPPSC Prelims 2001 (GS Paper I)