Based on this excerpt, Einstein’s “biggest mistake” happened when he
A changed his theory to accommodate a popular scientific view at the time.
B broke Edwin Hubble’s telescope.
C changed his field of study and decided to research dark matter instead of black holes.
D asked another student to help him write his thesis.
The correct answer is A changed his theory to accommodate a popular scientific view at the time.
Explanation: Einstein referred to his introduction of the cosmological constant as his “biggest mistake” because he did so to support the prevailing belief in a static universe, contrary to his original theory that allowed for an expanding universe. By adjusting his theory to fit this popular viewpoint, he later acknowledged that it was a significant error in his scientific reasoning. If you have further questions on this topic, feel free to ask!