Answer:
The answer to this question is given below in the explanation section.
Explanation:
Almost all app that is doing online business integrated third party payment gateway and login/services. But some apps, don't integrate the third party login/signin services such as go ogle or face book login/sign in services.
But in the context of this question, for a parking payment app, upon reservation of parking space, the pay option connects a user to a third party/external gateway. This gateway will accept payment from the user and upon confirmation of payment, the parking space will get reserved.
so the correct option to this question is:
While the other options are incorrect because:
The sign-in option does not connect the user to a third pay/gateway in case if the app has self-registration and sign-in functionality. Rate and Time remaining are features of the app that does not force the user to connect third-party gateway.