Securely prove your survey participation and control your data.
To selectively disclose and reuse the information you're providing during the study, you're going to need a cryptographic keypair, also know as an account (or referred to as "wallet" sometimes).
While being usable as a fully featured crypto wallet, signing up here is basically fully unrelated to interacting with a crypto currency - your account is simply a means of authentication against other system components that make use of blockchain technology or cryptography in general.