Consider the following statements about biomedical technologies:

(a) During open heart surgery blood is circulated in the heart-lung machine

(b) Blockage in coronary arteries is removed by angiography(c) Computerised Axial Tomography (CAT) shows detailed internal structure as seen in a section of body

(d) X-ray provides clear and detailed images of organs like prostate glands and lungs

Which two of the above statements are correct?