What’s the answer to this question

What is the best meaning for obscure in this line from the passage? a) ancient b) dark c) royal d) unknown

The missionaries who appear in the novel are colonists from britain portugal spain italy

Which of these sentences exhibits proper usage? a. many doctors affiliated with university hospital expressed concern about the policy (moore 5). b. many doctors affiliated with university hospital expressed concern about the policy (moore 5). c. many doctors affiliated with university hospital expressed concern about the policy (moore 5). d. many doctors affiliated with university hospital expressed concern about the policy (moore 5).