Which sentence is the best summary of the excerpt?

a Einstein opened our minds to amazing new possibilities and showed us that imagination is more important than knowledge.
b Scientists searched the skies for decades before they found the first real black holes.
c Karl Schwarzschild used his imagination when he thought about light and extremely distorted parts of space.
d Einstein’s idea that space bends inspired scientists to predict and later discover black holes.

excerpt:Einstein's idea of gravity had big consequences. It helped explain some observations that Newton's idea didn't account for. It also opened our minds to amazing new possibilities. For example, taking his cue from Einstein's idea that space bends, scientist Karl Schwarzschild began to think about what would happen if a place in space were extremely distorted. His light would follow the hyper-bent space, never to turn away from it. This was the first prediction of a black hole. At first, some scientists (including Einstein!) rejected Schwarzschild's ideas. Others were intrigued and began searching the skies for real black holes. Just decades later, they found the first of them. It just goes to show: sometimes, as Einstein himself once said, "Imagination is more important than knowledge."