premise: At a water carnival, each of the eight lifeguards—J, K, L, M, P, Q, R, and S—will participate in two events, a boat race and a rescue exercise. For each of these events the eight lifeguards are grouped into four two-person teams, subject to the following rules: If two lifeguards are teammates in the boat race, they cannot also be teammates in the rescue exercise. L and Q are teammates in the boat race. K and L are teammates in the rescue exercise. R and S are not teammates in either event. If M and P are teammates in the boat race and J and R are teammates in the rescue exercise, which one of the following is a pair that must be teammates in the boat race?
hypothesis: J and S