While surfing CNN I found this;
https://www.cnn.com/style/article/nasa-apollo-unseen-photos/index.html"There was one more management constraint for our mission that we followed perfectly," Cunningham recalls. "'Take no pictures of China.' That was an easy rule to follow. In 11 days and many passes over China, we never saw the surface because of the cloud cover and smog in their atmosphere."
A brief google search does not tell me why. Anyone know?
Ranb