Final answer:
A signal by R1 in or behind the neutral zone during a scrimmage kick typically indicates a legal fair-catch signal, which allows the receiver to catch the ball without interference. However, for the signal to be considered legal, it must meet certain criteria specified by the rules.
Step-by-step explanation:
A signal given by R1 in or behind the neutral zone during a scrimmage kick indicates a legal fair-catch signal. This signal is used in football to signify that the ball receiver elects to make a fair catch, which means that they get the opportunity to catch the ball without interference from the opposing team. Once the signal is made, no player from either team may initiate contact until the ball is caught.
However, if the signal given by R1 does not meet the specific criteria set forth by the rules, such as not being made clearly, it may be considered an illegal fair-catch signal. In the context of a scrimmage kick and the positions mentioned, the scenario likely entails a punt or kickoff where R1 intends to signal for a fair catch.