Incorrect!

You're driving behind a heavy goods vehicle. What should you do if it signals left but steers to the right?

Slow down and let the vehicle turn
Correct answer
Drive on, keeping to the left
Overtake on the right of it
You selected this answer
Hold your speed and sound your horn

DVSA theory test explanation

Large, long vehicles need extra room when making turns at junctions. They may move out to the right in order to make a left turn. Keep well back and do not attempt to pass them on their left.