In sentence 12 (reproduced below), which version of the underlined word best conveys the writer’s perspective on long space missions? With NASA’s attention directed to the problems of long space missions, it is certain that scientists will come up with creative solutions to the elevated risks to human well-being in space much as they have addressed dangers associated with shorter missions.

(as it is now)

(as it is now)
A

likely

likely
B

possible

possible
C

assured

assured
D

inconceivable