CTFL_SYLL_4.0 Question #19: Real Exam Question with Answer & Explanation

Consider the following user story about the authentication functionality of an e-commerce website: "As a logged-in user, I want to change my current password with a new one, so that I can make my account safer". The following are some of the acceptance criteria defined for the user story: [a] After the logged-in user has successfully changed his password, an email confirming the change must be sent to him [b] To successfully change the password, the logged-in user must enter the current password, enter a new valid password, and finally confirm by pressing the 'Change Password' button [c] To be valid, the new password entered by the logged-in user is not only required to meet the criteria related to the length and type of characters, but must also be different form the last 5 passwords of that user [d] A dedicated error message must be presented to the logged-in user when he enters a wrong current password [e] A dedicated error message must be presented to the logged-in user when he enters the correct current password, but enters an invalid password Based only on the given information, which of the following ATDD tests is most likely to be written first?