Indicate the true statements, and then reword the false statements so they are true.
a. Immunodeficiencies are associated with a decreased cancer risk.
b. Type I reactions are mediated by IgG antibodies.
c. Autoimmune disorders are not caused by type I hypersensitivities.
d. Systemic lupus is mainly mediated by a type III hypersensitivity.
e. A person with type 0- blood is called a universal donor.
f. Immunotherapies are useful to reduce type II reactions.