Can a pronoun be dropped in a list?

Towing insurance provides protection against collision damage to your automobile while you are attaching (it) to, towing (it) by, or detaching it from a covered rental truck or while it is loaded onto, transported, or unloaded from a covered rental trailer.

Can you explain why the pronoun 'it' (indicated in bracket above) can be omitted from the list used as above?

Edit
Answer analysis are as follows:

Towing insurance provides protection against collision damage to your automobile while being attached, towed, or detached from a covered rental truck, or loaded onto, transported, or unloaded from a covered rental trailer

(A) while being attached, towed, or detached from a covered rental truck, or loaded onto, transported,

Incorrect due to lack of pronoun and be verb, making 'insurance' the subject of the verb 'attach'. There is also a lack of a parallel marker after 'or': While [it is] being...., or [While it is]

(B) while you are attaching to, towing by, or detaching it from a covered rental truck or while it is loaded onto, transported,

This option correctly refers 'automobile' [it] as the subject of the verb 'attach...'. Correct use of parallelism.

(C) when attached to, towed by, or detached from a covered rental truck or when it is loaded onto, transported by,

Same as A. Lack of pronoun referring to 'automobile', thus making 'insurance' the subject of the verb 'attach'. Incorrect parallelism.

(D) while you being attached to, towed by, or detached from a covered rental truck or loaded onto, transported by,

Similar to A and C. Wrong use of pronoun, aking 'you' subject of the verb 'attach'. Omission of parallel marker.

(E) when being attached to, towed by, or detached from a covered rental truck or loaded, transported,

Same as A and C, wrong subject and parallelism.

Hope this helps and please feel free to correct me if any of the above is incorrect!

(B) is incorrect. You need either:

attaching to / towing by / detaching from a covered rental truck

or

attaching it to / towing it by / detaching it from a covered rental truck

You also need a preposition here:

loaded onto, transported by, or unloaded from a covered rental trailer

Assuming this insurance is held by the tow truck operator (not the automobile owner), this is correct-ish*:

Towing insurance provides protection against collision damage to an automobile while you are attaching it to, towing it by, or detaching it from a covered rental truck or while it is loaded onto, transported by, or unloaded from a covered rental trailer.

*Stylistically, the while clauses should both use the same voice—active or passive—and the same aspect—progressive or simple. Try this instead:

Towing insurance provides protection against collision damage to an automobile while it is being attached to, towed by, or detached from a covered rental truck or loaded onto, transported by, or unloaded from a covered rental trailer.