You are a network administrator of an Active Directory domain named contoso.com. You have a server named Server1 that runs Windows Server 2012. Server1
has the Web Server (IIS) server role installed. Server1 will host a web site at URL https://secure.contoso.com. The application pool identity account of the web site
will be set to a domain user account named AppPool1. You need to identify the setspn.exe command that you must run to configure the appropriate Service
Principal Name (SPN) for the web site. What should you run? To answer, drag the appropriate objects to the correct location. Each object may be used once, more
than once, or not at all.
Select and Place:
Answer: 
setspn.exe -s http/secure.contoso.com AppPool1
https://support.microsoft.com/en-us/help/929650/how-to-use-spns-when-you-configure-web-applications-that-are-hosted-on
https://technet.microsoft.com/en-us/library/cc731241.aspx#BKMK_examples
But the the URL form question is: https://secure.contoso.com (SSL) and in your awser it just http.
If think the anserw should be:
setspn.exe -s https/secure.contoso.com AppPool1
Taken from Microsoft (first link that Sultan shared):
“The HTTP service class differs from the HTTP protocol. Both the HTTP protocol and the HTTPS protocol use the HTTP service class.”
if you tried to use https/… it would give you an error message. http/ covers both http and https