Bumblebee served under him . Bulkhead was in charge of all of Cybertron 's space bridges . And Ratchet was retired on some quiet planet with a pink and white femme that he 'd known from before . They were all gone .
According to the above context, choose the best option to answer the following question.
Question: What may have been true of them in the past ?
Options:
A. They all worked together on a team .
B. None of the above choices .
C. They had served on a quiet planet .
D. They had met once on a bridge .


A