Which statement identifies two technological advancements during the period between 1980 and 1989? (3 points) Select one:
a. The first successful orbiting satellite and several spacecraft were launched.
b. The first human was sent into space, and water was discovered on Mars.
c. Numerous spacecraft were launched, and humans landed on the moon.
d. Robotic spacecrafts and twin Voyagers were launched to gather data from distant planets.