Final answer:
Phagocytes like macrophages and neutrophils play a critical role in the immune response by engulfing pathogens and sequestering iron to hinder pathogen growth. They also produce chemicals that promote inflammation and release cytokines to attract other immune cells.
Step-by-step explanation:
The key actions taken by phagocytes in the immune response to invading pathogens are encapsulated in the option C) Deploy and destroy invaders; Sequester iron in blood. Phagocytes, such as macrophages and neutrophils, are integral to the body's defense mechanisms. These cells serve by engulfing pathogens through a process known as phagocytosis, effectively neutralizing the threat posed by these foreign entities. Furthermore, phagocytes assist in sequestering iron to limit its availability to invading pathogens, thereby inhibiting their growth.
Macrophages are also known for their roles in producing chemicals that foster inflammation, which helps to control infection by attracting more immune cells to the site of infection. Neutrophils, another type of phagocyte, are typically the first responders during an infection and release cytokines to further recruit and activate other cells of the immune system.