Which excerpt from neruda’s “your laughter” contains an example of a metaphor?

“your laughter must raise / its foamy cascade”
“my love, in the darkest / hour your laughter / opens”
“i want your laughter like / the flower i was waiting for”
“because your laughter / will be for my hands / like a fresh sword.”

“because your laughter / will be for my hands / like a fresh sword.”

Explanation:

Metaphor is a figure of language in which one uses a word or an expression in a sense that is not very common, revealing a relation of similarity between two terms.

In this case, the author of the phrase is establishing a relationship of resemblance between a smile and a sword.  He meant that the smile of his beloved makes him powerful in the same way that a sword would leave.

''your laughter must raise / its foamy cascade''

Explanation:

We need to remember that Metaphors DO NOT use like or as in their figurative illustrations, these are called similies. Metaphors make a direct comparison. As seen in the answer Neruda makes a direct comparison of the person's laughter to a Foamy cascade as it rises. It has no mention of like or as.

a.) it provides a clue to solve the mystery.