POSSESSIVE+DOING. old question, new knowledge.

[thanghnvn]

The 2 followings are from gmatprep absolutely.

some times, possessive+doing is considered correct, other times, incorrect. I am confused.

After several years of rapid growth, the healthy care company became one of the largest health care providers in the metropolitan area,// while it then proved unable to handle the increase in business, falling months behind in its payment to //doctors and hospitals.

A. while it then proved unable to handle the increase in business, falling months behind in its payment to
B. while it then proved unable to handle the increase in business and fell months behind in its payment to
C. but then it proved unable to handle the increase in business, falling months behind in its paying
D. but then proving unable to handle the increase in business, falling months behind in paying
E. but then proved unable to handle the increase in business, falling months behind in paying
oa E.
and

Thirteen states from all regions of the country announced a plan// to impose new controls on pollution from truck and bus engines in that they will jointly adopt// eission limits that would be far stricter than the federal rules.
A to impose new controls on pollution from truck and bus engines in that they will jointly adopt
B to impose new controls on truck and bus engines' pollution by the joint adoption of
C to impose new controls on pollution from truck and bus engines, and jointly adopting
D for imposing new ontrols on pollusion from truck and bus engines, and jointly adopting
E for imposing new controls on truck and bus engine pollution in the joint adoption of
oa D.

I have an idea.
because "doing" emphasize that the subject causes the action of "doing", "adopting" is considered correct in the second question. Ron explain this clealy in his video.

regarding the fist question.
because "doing" emphasize that the subject cause the action of "doing", "its paying" in C in the first question is considered REDUNDANT ( only "paying" shows "the company" and we do not need "its"). This redundancy make C wrong. This cases happen frequently. that is why

BE CAREFULL WHEN POSSESSIVE+DOING IS USED. REDUNDENCY CAN BE AN ERROR.

C is not wrong because we should use NOUN not"doing" when the noun exist.

we use "doing" to emphazise that the subject causes the action of "doing" . we use NOUN to say of general thing. Ron said this clearly in his video.

of course, if NOUN dose not exist, we have nothing to discuss and have to use DOING all the times.

We will not have the rule " we should use NOUN not DOING if NOUN exist" because there are only 2 cases. when the subject causes the action, we use DOING. When the action is general, we use NOUN. There must not be a preference of NOUN.

anyone see a question in og book in which "noun" is prefered over "doing", pls, speak out.

experts, members, pls, confirm/ comment.

[tim]

neither of your examples contain a possessive-doing construction, and the "answers" to both are incorrect as you have transcribed them..