hello? ^^

I am wondering which is correct.

A :Why didn't you walk to the hospital.

B: I lived in an isolated mountain village, so _________ to the hospital wasn't an option.

(a) running

(b) to run

the correct answer is (a)

but I can't see why (b) isn't possible.

please help....
The choice between a gerund (-ing) and an infinitive (to ...) for the subject of a sentence is usually made in favor of the gerund. The infinitive is sometimes used for a sentence that expresses an "eternal verity" or a future potentiality (To err is human.) but for most ordinary conversation, the gerund is used as subject.

In this scenario, you'd fill with a past continuous tense rather than a present perfect tense. Hence "running" is the correct answer since, its all over (past).

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thanks for quick reply ^^
 CalifJim's reply was promoted to an answer.
thanks for kind reply ^^ thank you.
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