Two Events Occur 100 M Apart with an Intervening Time $\mu$

Multiple Choice

Two events occur 100 m apart with an intervening time interval of 0.37 $\mu$ s. The speed of a clock that measures the proper time between the events is:

A) 0
B) 0.45c
C) 0.56c
D) 0.90c
E) 1.8c