Lead generation for a PDF

Hello Community,

regarding CTA buttons and creating a pdf lead I read a lot of the older articles in the community.
What would be your quick best practice to set up an easy lead generating pdf download?

I want visitors to fill out a form to receive a pdf afterwards
My ideas are:

a) Set up an Unbounce form and link the PDF download on the confirmation page
Is it possible to “check” if it’s a trashmail or the user just put in nonsense to get to the confirmation page?

b) Set up an Unbounce form and sent them an email with a download link. This way people have to use a valid email to receive the email
I guess it is not possible to have the email sent out to the email adress via Unbounce, right?

c) Integrate a 3rd party form

Thanks for your opinions and guidance