page.all(:link,"Graduation") returns Ambiguous match, found 2 elements matching link "Graduation"
That means page contains multiple graduation text link.so if you want to click the first one you can write like this
page.all(:link,"Graduation")[0].click
It will click the first link and the below one click the second link.You can use anyone as your needs.
page.all(:link,"Graduation")[1].click
am sure this will work for you