Haemoglobin is 1. The colouring matter of leaves of plants 2. The colouring matter of blood 3. A compound that is highly coloured 4. A compound that contains iron The correct answers are: (a) 1, 2 and 4 (b) 2, 3 and 4 (c) 1, 2, 3 and 4 (d) 1, 2 and 3