Given below are four statements (a-d) regarding human blood circulatory system:
| (a) |
Arteries are thick-walled and have narrow lumen as compared to veins |
| (b) |
Angina is acute chest pain when the blood circulation to the brain is reduced |
| (c) |
Persons with blood group AB can donate blood to any person with any blood group under ABO system |
| (d) |
Calcium ions play a very important role in blood clotting |
Which two of the above statements are correct?
| 1. |
(a) and (b) |
2. |
(b) and (c) |
| 3. |
(c) and (d) |
4. |
(a) and (d) |