Captain Jirk Reports to Headquarters That He Left the Planet

Multiple Choice

Captain Jirk reports to headquarters that he left the planet Senesca 1.88 × 10⁴ seconds earlier. Headquarters sends back the message: "Was that spaceship proper time?" It will be spaceship proper time if it was

A) measured by one clock fixed at one spot on Senesca.
B) measured by one clock fixed at one spot on the spaceship.
C) measured by a clock on Senesca at departure and by a clock on the spaceship when reporting.
D) measured by a clock on the spaceship when departing and by a clock on Senesca when reporting.
E) calculated by dividing the distance from Senesca according to Senesca by the speed of the spaceship.