Did Officer Morris Need a Search Warrant to Look at the Text

Did Officer Morris need a search warrant to look at the text messages on Ned's phone

A) Yes, a warrant is required prior to the search of any type of electronic device.
B) Yes, a cell phone is considered a closed container.
C) No, the text messages were the property of the sender not Ned.
D) No, officers are allowed to search cell phones if they are on the person or in the area under the person's immediate control at the time of the arrest.