The simplest and best verb for dialogue attribution is said. Plain and simple, and — as I think I’ve mentioned here before — effectively invisible. Other verbs like replied, stated, mentioned, affirmed, and the like are also valid, but should be used sparingly and in proper context. Replied only works when the speaker is responding directly to something somebody else has just said, for instance, and stated goes with declarative sentences in which a fact or opinion is being asserted.
And then there are the verbs which are not meant for dialogue attribution at all. Smile, for example. People don’t smile things, they say them. They may say them smilingly, or say them, smiling, but smile does not equal say and shouldn’t be used as if it does. The same goes for any other gesture or facial expression — no shrug or wink or grimace is the equivalent of speech.
I’m just sayin’.