The question is from Official Guide 2012. I understand that since is incorrect usage here because it refers back to time. Can you please explain why option B is incorrect? I think it might be lack of conjunction between reason for naming and rest of sentence ("and their").Besides, by whom ...

Hello,
I am still not clear why option B is incorrect. I rejected option B because of "have emerged" .The picture being singular ,it should have been has .
Please advise if there are any other reasons.


Thanks