Question #N816

Former astronaut Ellen Ochoa says that although she doesn’t have a definite idea of when it might happen, she ______ that humans will someday need to be able to live in other environments than those found on Earth. This conjecture informs her interest in future research missions to the moon.

Which choice completes the text with the most logical and precise word or phrase?
A. demands
B. speculates
C. doubts
D. establishes