Final answer:
The body's immune response to a wound infection involves leukocytes, which are white blood cells that fight off pathogens. Platelets assist in clotting, but leukocytes are specifically responsible for combating an infection.
Step-by-step explanation:
When an injury occurs and an infection develops in a wound, the body's immune system responds to fight the infection. One key component of blood involved in the immune response is white blood cells, known as leukocytes. These cells specialize in identifying and destroying pathogens that enter the body. While platelets (thrombocytes) are critical for clotting and preventing blood loss, and red blood cells (erythrocytes) transport oxygen, leukocytes are the ones that act as the body's defenders against infection. Therefore, the answer to which component of blood works to fight an infection is B. Leukocytes.