Studying an environmental science degree provides you with a broad understanding of current environmental issues and challenges on a local, national and global scale. You learn about the impact humans have on the environment and how to manage it.
Hello. You did not show line 4 to which the question refers, which makes it impossible for the question to be answered accurately, but I will try to help you in the best possible way.
The definition "Showing great intelligence" will be the correct one if line 4 presents a text referring to smartness, academic quality and wisdom.
The definition "Full of light" is correct if line 4 has a text on clarity, lighting and brightness.
The definition "Excellent or superior in performance" will be correct if line 4 presents a text about something or someone who has a great capacity to complete activities in an amazing way.
It would be a subordinate cause, for it can't stand on its own. Think about it: Since early this morning. What happened since early morning? Since it doesn't provide that information, it wouldn't be able to be an independent cause.
Also, I don't believe that the sentence is grammatically correct :)