That’s a very different question. A smartphone can to some degree emulate the other devices listed so when people are asked to pick only one device most are naturally going to choose that even if it’s not currently their primary device, and since they could only choose one it’s not useful in determining how many people use other devices. It also appears to be a follow-up question asking about second most important devices so it’s definitely not useful out of context.

From that survey question alone you cannot reasonably claim which device is used most often.