A.

The THE, TRP2, and ERP 1 genes are located next to each other on a single chromosome and are organized into an operon.

B.

The THE, Z'RP2, and 'RPI genes may be located on different chromosomes but are activated by the same transcription factor.

C.

The THE, Z'RP2, and ERP 1 genes are identical genes since they are activated by the same transcription factor.

D.

The THE, TRP2, and TRP1 genes may be located on different chromosomes but with identical operator sequences.