In the following passage, some words have been deleted. Read the passage carefully and select the most appropriate option to fill in the blanks.
Blood transfusion is a procedure that starts with the doctor (1)_______ the patien’t sblood type. In case of a wrong transfusion in the immune (2)_______ of an individual, it leads to an infection.

A

settling; order

B

treating; process

C

determining; system

D

diagnosing; structure