In which direction does the DNA-dependent RNA polymerase catalyse the polymerisation ?

Only 3’ → 5’ . only 5’ → 3’ . Both (a) and (b). None of these .

only 5’ → 3’ .

The two strands have opposite polarity and the DNA-dependent RNA polymerase also catalyse the polymerisation in only one direction, that is, 5'→3', the strand that has the polarity 3'→5' acts as a template, and is also referred to as template strand.