What figure of speech is used in "White smoke crept over a green field." Alliteration
Idiom
Simile
Personification

Personification

Explanation:

Alliteration means the occurrence of the same letter or sound at the beginning of adjacent or closely connected words.

Idiom means a group of words established by usage as having a meaning not deducible from those of the individual words.

Simile means a figure of speech involving the comparison of one thing with another thing of a different kind, used to make a description more emphatic or vivid.

Personification means the attribution of a personal nature or human characteristics to something nonhuman, or the representation of an abstract quality in human form.

So the answer is personification because "White smoke crept over a green field." is the attribution of a personal nature characteristics.

c.caliberate the new thermometer and begin the experiment again