The bottom wave has a greater amplitude.
Given the information that the first wave has a lower number of cycles (indicating lower frequency) than the second wave, but both waves travel an equal horizontal distance in one second, we can conclude that the bottom wave, which has a greater amplitude, does not have a lower frequency than the second wave. Furthermore, since the second wave has more cycles in the same time frame, it has a higher frequency. Thus, the correct completion of the statement is that the bottom wave has a greater amplitude.