Types of Serology test

I'm not sure with the following questions. Can anyone help me out? thnx

The direct ELISA (Enzyme-Linked Immunosorbent Assay) is useful to detect the presence of a specific antigen. To do so, you would need
- antibodies specific for that antigen absorbed onto a plate
- an enzyme which reacts with the antigen
- additional antibodies which can bind the enzyme-antigen complex
- all the above are required

I know direct elisa is something that detects a certain antigen and the indirect is a specific antibodies. So in this question, I chose the 2nd one. But please check this.

The Western blot
- is used to detect some specific protein
- uses an enzyme-linked antibody to that protein
- can generate a color reaction using the enzyme to convert a substrate to a colored product
- all the above

I gave up on this one. I think the third one could be right. not sure about the others