Question regarding modification E-gmat

Another question is here:

I studied E-Gmat concepts for modification 4 months ago, and when I studied the concept again I noticed slight changes. In the past, (for VERBing) it mentioned clauses preceded by comma etc. But now, it talks about the Doer of actions when it modifies the action. However, maybe it was changed for better explanation.

I have this question now:

It is called a sea, but the landlocked Caspian is actually the largest lake on Earth, which covers more than four times the surface area of its closest rival in size, North America's Lake Superior.

A. It is called a sea, but the landlocked Caspian is actually the largest lake on Earth, which covers
B. Although it is called a sea, actually the landlocked Caspian is the largest lake on Earth, which covers
C. Though called a sea, the landlocked Caspian is actually the largest lake on Earth, covering

D. Though called a sea but it actually is the largest lake on Earth, the landlocked Caspian covers
E. Despite being called a sea, the largest lake on Earth is actually the landlocked Caspian, covering

1) As per my understanding, "covering" cannot modify the noun "landlocked Caspian" since it needs to be placed next to it. So, per this structure, we have a modifier that modifies an action.
2) However, we have no verb in the sentnce except the helping verb "is". So my question is, can a modifier that modifies an action, modifies a helping verb? (if yes, then can we say that the Doer of "is" and "covering" is the same? which is Landlocked Caspian?"

Please refer to the picture attached for the concept file.

Moreover, (when looking at the attached summary). The part "covering ...", is it considered a result or a description?

If I have any mistake in my understanding please correct me. I tried my best to explain every single detail to help you identify my mistakes if any.

Note: I am not saying that Choice C is incorrect, I solved it correctly but I need to strengthen my understanding of VERBING modifiers.