Which statement best explains how to identify the text structure used in the excerpt from "for want of a horseshoe nail"?

from a bar of iron he made four horseshoes. then he hammered and shaped and fitted them to the horse’s feet. then he began to nail them on. but after he had nailed on two shoes, he found that he did not have enough nails for the other two.

the text structure is compare and contrast; the words made and began indicate this.

the text structure is sequence; the words then and but after indicate this.

the text structure is cause and effect; the words found that and enough indicates this.

the text structure is problem and solution; the words hammered and fitted indicate this.