Apatient is having surgery to replace her bone marrow because it does not function properly. the patients body most likely has an inability to

Fight infections

Explanation:

Hematopoietic multipotent stem cells present in bone marrow produce two types of stem cell: myeloid and lymphatic stem cells. These stem cells give rise to all types of white blood cells including granular and agranular leukocytes. Since the white blood cells serve in immune responses by fighting infections, malfunctioning of bone marrow would weaken the ability of person to resist infections.