Where else would we have the opportunity to meet an astronaut or touch a rock from the moon? (3) We could learn all about space travel and the
Solar System (4) Exhibits display space suits worn by astronauts as well as replicas of a shuttle and a space laboratory


What change if any should be made in sentence (3)?
A Change could learn to could have learned
B. Insert a comma after travel
C. Change Solar System to solar system
D. No change is needed