When the cell is NOT in the presence of tryptophan,

A. RNA polymerase can transcribe mRNA.
B. the repressor proteins bind to the operator.
C. structural genes are not transcribed.
D. the repressor proteins are active.

[34 points awarded to the best answer, use facts and/or data] 1.) what's the likelihood of thunderstorms occurring in the state of maryland? {this question is for a project for science, use facts and/or data and explain why . 34 points to the best answer]