Dynamic fields on SharePoint

Hi,

I am a SP rookie and I must create a dynamic list on SharePoint.

I have the following columns:

• Dynamic (choice, checkboxes - 3 options (A, B, C)),
• Question A1, Question A2, Question B1, Question B2, Question C1, Question C2 (single line of text)

This is what I would like it to do: upon entering a new item, the questionfields to be hidden or disabled and if the user checks option A, the form displays teh fields Question A1, Question A2. Or if the user checks options A and B the form displays the fields AI, A2, B1, B2 (and so on for any possible combination of checkboxes).

Can this be done using SP Designer or directly on the SP site?