In preparation for the prediction of a major earthquake that will hit the state, a satellite-based computer network is being built by the California Office of Emergency Services for identifying earthquake damage and to pinpoint the most affected areas within two hours of the event.

(A) In preparation for the prediction of a major earthquake that will hit the state, a satellite-based computer network is being built by the California Office of Emergency Services for identifying

(B) In preparing for the prediction that a major earthquake will hit the state, the California Office of Emergency Services is building a satellite-based computer network that will identify

(C) In preparing for a major earthquake that is predicted to hit the state, the California Office of Emergency Services is building a satellite-based computer network to identify

(D) To prepare for the prediction of a major earthquake hitting the state, a satellite-based computer network is being built by the California Office of Emergency Services to identify

(E) To prepare for a major earthquake that is predicted to hit the state, the California Office of Emergency Services is building a satellite-based computer network that will identify

[spoiler]OA: C[/spoiler]

I have two questions:

i) Why does C use "in preparing" and not "in preparation"? Would that have been better.

ii) "to prepare" in D and E is an infinitive phrase. What is the property of such such phrases? Do such phrases modify the word next to the infinitive phrase or are these adverbial?

Thanks in advance.