They are a species, the definition is:
A group of organisms that have similar characteristics and can interbreed to produce fertile offspring
The correct answer I believe is C, but please correct me if I’m wrong!
An average person (let's say one that weights 70 kg) has about 5.5 liters of blood (that's a little more than 160 ounces or 1.2 to 1.5 gallons). Other way of saying this is : about 7% of body weight.
