function as a subject: to-infinitive vs. gerund

Hi,

The sentence below is from the book I’m studying with:

____________ oil from the north to the south has been recommended as a way of easing the present energy shortage.

(a) To pump
(b) Pumping

The answer is (b). but I cannot understand why (a) cannot be the one. I mean, I think both are right for the blank.

When I was in school, my professor once said to infinitive had a future feature while gerund had a past one as we saw the sentences with ‘regret’. For example,

  1. I regret having done that. (=I regret that I did that.)
  2. I regret to have to do that. (= I feel sorry/regret that I will have to do that.)

So I thought, maybe, ‘pumping’ is more right answer for the blank because it(=pumping oil from the north to the south) has been recommended - it means it “was” recommended at a point in the past. That’s why gerund is more proper than to infinitive… this is my conclusion.

What do you think? Maybe I’m making a broad interpretation. Would you tell me why the gerund is proper for the blank?

Thanks,
sweetpumpkin

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I seldom consider the ‘potentiality’ vs ‘activity’ distinction between infinitive-as-noun and ing-form-as-noun. In this case, the infinitive is usually quite awkward as a subject in the initial position in a sentence; in addition, notice the parallel structure of ‘pumping’ and ‘easing’.

With your 2nd set of sentences, I do not find #2 correct at all. ‘Regret’ always takes the -ing form, to my mind.
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