We have the following information about the patients:
A) Healthy 40-year-old man
B) 18-year-old girl with chronic lung infections
C) History of anemia
And for each tube, we have the values for hemoglobin and leucocytes.
Hemoglobin is found in the red blood cells and helps carry oxygen, so a person with anemia would have low levels of hemoglobin.
In this case, tube 3 has the lowest levels of hemoglobin, out of range for both males and females, so we can say it belongs to patient C.
This leaves us with tubes 1 and 2.
If we see the levels of hemoglobin, tube 1 has lower levels of hemoglobin than tube 2, which suggests that tube 1 belongs to a female and tube 2 to a male.
But we also have to take into account the leucocyte, which would be elevated in the case of an infection. If you look at this, tube 1 has elevated leucocytes.
Combined, this information tells us that tube 1 belongs to patient B and tube 2 belongs to patient A.