Re original question: answer b is correct based upon:
1) In Northern hemisphere
2) Geostrophic (so winds follow the isobars)
3) Low pressure (so flow anti-clockwise)
So, imagine you are 'flying' an anti-clockwise circle around the centre of the low. You are currently flying 020T. Therefore, the centre of the low will be 90 degrees to your left. 020-90 (360+20-90) = 290.