Answer:
The role of a "leader sequence" is to B. determine whether transcription can proceed through the genes in the operon.
Step-by-step explanation:
The "leader sequence" is the 5′ untranslated region (5′ UTR). Its main function is the regulation of translation of a transcript using different mechanisms. They differ depending we are talking about eukaryotes or prokaryotes (more complex). It determines whether transcription can proceed through the genes in the operon. The operon is is a functioning unit of DNA that is made of a cluster of genes under the control of a single promoter.