Concerning the Two Immunofluorescence Methods of Diagnosing Viral Infection, Which

Concerning the two immunofluorescence methods of diagnosing viral infection, which statement is correct?

A) Direct immunofluorescence is generally more rapid and specific than indirect immunofluorescence.
B) Direct immunofluorescence is best suited to situations in which large quantities of virus are suspected.
C) Signal amplification of the indirect test decreases specificity by increasing nonspecific background fluorescence.
D) Indirect immunofluorescence should be used when lower quantities of virus are suspected, such as for detection of respiratory viruses in specimens from adult patients.
E) All of the above are correct.