A drop of each of the following, is placed separately on four slides. Which of them will not coagulate?

Options

(a) Blood serum
(b) Sample from the thoracic duct of lymphatic system
(c) Whole blood from pulmonary vein
(d) Blood plasma.

Correct Answer:

Blood serum

Explanation:

Blood serum is liquid minus clotting elements of pale yellow colour. It does not have fibrinogen and other clotting materials. It does not take part in blood clotting.