A Latex Agglutination Test Is Done for Legionella Antigen

A latex agglutination test is done for Legionella antigen. Reactions were as follows:latex particles coated with murine anti-Legionella + specimen = 2+ agglutination
latex particles coated with murine anti-Legionella + positive control = 2+ agglutination
latex particles coated with murine anti-Legionella + negative control = no agglutination
latex particles coated with non-specific murine antibodies + specimen = 2+ agglutination
What is the best interpretation of this set of data?

A) This specimen may have heterophile antibodies or other cross- reacting species and should be tested by another method.
B) The specimen is negative for Legionella antigen.
C) The assay must be repeated because the positive and negative controls appear to have been mixed up.
D) The specimen is positive for Legionella antigen.