Why did movies gain popularity when stage plays were available? A. Going to the movies didn't require dress clothes. B. Movies cost less money. C. Movies could reach more people. D. All of the above are correct.

To determine why movies gained popularity when stage plays were available, let's analyze each option: A. **Going to the movies didn't require dress clothes.** - This is true; movies were often seen as a more casual form of entertainment compared to the formal atmosphere of stage plays. B. **Movies cost less money.** - This is also true; movie tickets were generally more affordable than tickets for live theater performances, making them accessible to a broader audience. C. **Movies could reach more people.** - This is correct as well; movies could be shown in multiple theaters simultaneously and could be distributed widely, allowing them to reach a larger audience than a single stage play. D. **All of the above are correct.** - Since all the previous statements (A, B, and C) are true, this option is also correct. Given this analysis, the answer is: **D. All of the above are correct.**