Observe the Flow Cytometry Cross- Match Protocol in the Table

Observe the flow cytometry cross- match protocol in the table and interpret it. FITC is fluoroscein isothiocyanate which fluoresces green, and PE stands for phycoerythrin which fluoresces red.

A) This is a positive B cell cross- match.
B) This procedure must be repeated because it was performed incorrectly.
C) This procedure must be repeated because no fluorescence was detected in tube 1.
D) This procedure must be repeated because both fluorochromes were detected in tube 2.
E) This is a positive T cell cross- match.