Which of the following usually binds to DNA in a sequence sp

Which of the following usually binds to DNA in a sequence specific manner?

RNA polymerase core enzyme

RNA polymerase core enzyme + sigma factor

dsrA ncRNA

23s rRNA

Solution

RNA polymerase core enzyme + sigma factor binds to DNA in a sequence specific manner. Because sigma subunit enables the RNA polymerase to recognize the promoter site. The sigma factor is a sequence specific binding unit.