I think an education guess for this one because he is thinking about what to guess probably.
The scheme whereby occupants in a pair of shuttles is as follows
use a strong cable with large weight on the end
Then use the orbital naneuvering system(OMS) to set the whole work as spinning about their common center of gravity.
It might be 144.2 m but i’m not for sure:)
KE= 1/2MV^2 - equation
KE= 1/2 (2 kg)(15 m/s)^2 - plug it to the equation
KE= (1 kg)(225 m/s) - multiply
KE= 225 J - Answer (letter D)
Hope this helps