Setting up for TAX as a freelancer: Help please!

Hi all!

I filled in the TR1 form and sent it to revenue and they sent me a document titled "Tax Returns and Payments" telling me to signup with ROS. When I go onto ROS, one of the first thing it asks me to do is to apply for a ROS ACCESS NUMBER. To do this one needs to select the "Tax Type/Approval No." and this is where I get confused. Since I am a freelancer and "Sole Trader", am I to select "Income tax" here or "VAT"?

The form that the revenue office sent back to me does not specify this but merely gives a list of all the possible types of tax and asks me to select the relevant one during my signup process.

Please could someone help me?

thank you in advance