The important features of the transactional model of communication are

The important features of the transactional model are that it is mostly used for interpersonal communication, that senders and receivers can interchange their roles, and that feedback is simultaneous.

Statement 2 fits because the model best captures close, face-to-face person-to-person exchange.

Statement 3 fits because the parties act as communicators who swap the sending and receiving roles freely.

Statement 4 fits because response flows back at the same time as the message, not after a gap.

The idea that feedback is merely repetitive misses the model's stress on ongoing, real-time response.

The idea that a heavy dose of noise supplies a message distorts noise, which hinders rather than carries meaning.