Final answer:
The assassination of Robert F. Kennedy was not linked to the assassination of MLK.
Step-by-step explanation:
The assassination of Robert F. Kennedy was not directly linked to the assassination of MLK. The two events occurred on different dates and were carried out by different individuals. Sirhan Sirhan was responsible for assassinating Robert F. Kennedy, while James Earl Ray was responsible for assassinating MLK. Therefore, option (a) They were not linked, is the correct answer.