Why does UAC prompt for a password instead of yes/no?

Until today, when I started Command Prompt as an administrator, I would get a yes/no prompt like (image copied from web):

enter image description here

Today when I start a Command Prompt as administrator, I get a prompt like this (the one I get also allows me to enter a PIN):

enter image description here

What controls whether Windows 10 presents a UAC yes/no prompt versus a UAC password/pin prompt?

From the answer linked by BigChris, it looks like the yes/no prompt is called "Admin Approval Mode".

This is controlled through the local policy. Launch Local Group Policy Editor (Run > gpedit.msc) and expand Local Computer Policy > Windows Settings > Security Settings > Local Policies > Security Options. Scroll to the bottom of the content window and look for User Account Control: Run all administrators in Admin Approval Mode.

In my case, I removed and added my account to the administrators group. After that you have to logout and log back in to get the UAC prompt without the password.

Further to Andomar's answer, another setting you can change instead (in the same location) is User Account Control: Behaviour of the elevation prompt for administrators in Admin Approval Mode.

The options are: