568 muons were counted by a detector on the top of mount washington in a one hour period of time. assuming moving muons keep time at the same rate as stationary muons, then 27 should survive until sea level. the fact that 412 muons were detected by the same equipment at sea level reveals that
a. the stationary clock measures time differently at different altitudes
b. the moving clocks keep time at the same rate as stationary clocks
c. that moving clocks run slower
d. that moving clocks run faster