Option 1: No Blood - This option is incorrect. Prawn hearts do carry blood.
Option 2: Deoxygenated Blood - This option is incorrect. Prawn hearts do not carry deoxygenated blood as they do not have lungs like higher organisms.
Option 3: Oxygenated Blood - This option is correct. Prawn hearts carry oxygenated blood. Prawns have a simple circulatory system where blood is pumped from the heart to the gills to be oxygenated and then circulated to the rest of the body.
Option 4: Mixed Blood - This option is incorrect. Prawn hearts do not carry mixed blood as they do not have a separate pulmonary and systemic circulation like mammals.
In conclusion, the correct answer is option 3, as prawn hearts carry oxygenated blood.