Best practice UX – selecting item from couple of items

I'm working on a website. In one of my forms I need to select the form type (depending on the form type the rest of the fields will change their behavior, e.g. the disabled status and their placeholders).

There are only two available types: "type A" and "type B".

I am wondering what the best practice/rule of thumb is in this case.

I can think of these options (although I'm sure there are additional options I haven't thought about):

1. Drop-down list (html <select> tag)

This is a good option since I could add additional types in the future; however, it doesn't look so nice.

2. Radio buttons (html <input type="radio"> tag)

This option also allows me to add additional types in the future, but it occupies more than one line (of my form) which I don't like (all the rest of the form fields occupies single lines).

3. Toggle slider (html <input type="checkbox"> tag with some style to look like a slider)

This option is a checkbox (behind the scenes); therefore I can toggle between only two options. However UI-wise it looks great.

P.S I'm using material design in my site so material components can be a valid solution (however, the question isn't directly related to it).