In the following sentence, a part of the sentence is underlined. Below are given alternatives to the underlined part, which may improve the sentence. Choose the correct alternative. In case no improvement is needed, choose the option that indicates 'No improvement'.

When Benjamin Franklin invented the lightning-rod, the clergy condemned it as an impious attempt for defeat of God's will.

A. To defeat God's will

B. At defeat of God's will

C. At defeating the will of God

D. In defeating God's will