Since a sail is the part of a sailboat that propels it forward, we need to pick out an answer choice that describes what part of a carriage propels it forward. While "horse," "door," and "axle" are each components of a carriage, it is a horse that propels a carriage forward by pulling it, so "horse" is the correct answer.

Words are the constituent parts of sentences, so we need to pick out an answer choice in which the first word is the constituent part of the second. While "paragraph is to sentence" and "book is to page" might each look potentially correct, sentences make up paragraphs and pages make up books, not the other way around as the answer choices are listed, so neither of those answers can be correct. Letters make up words just as words make up sentences, however, so "letter is to word" is the correct answer.

A shoelace is part of a tennis shoe, so we need to pick out an answer choice in which the second word is a part of the first word. Of the potential answer choices, "beak is to bird" and "blubber is to walrus" might each look like potentially correct answers, but because each of those answers's words are in the wrong order, neither can be the correct answer—birds are not part of beaks, but the other way around, and neither are walruses part of blubber. "Computer is to keyboard," however, is the correct answer, because just as shoelaces are part of tennis shoes, keyboards are part of computers.

A chapter is a subdivision of a book, so we need to pick out an answer choice in which the first word is a subdivision of the second. While “week is to month” and “day is to hour” might each look like a potentially correct answer, a day is not a subdivision of an hour, so “day is to hour” cannot be the correct answer. A week is a subdivision of a month, however, just as a chapter is a subdivision of a book, so “week is to month” is the correct answer.

An "army" is a group of soldiers lead by a general, so to solve the analogy, we need to pick out an answer choice that describes the person who leads a "team." A "captain" leads a "team," so "captain" is the correct answer.

The relationship in "sleeve is to shirt" is part to whole. The best choice is "branch is to tree" because a branch is a part of a tree. The choice "car is to wheel" demonstrates the same relationship, but the words are in the reverse order of whole to part rather than in the order of part to whole as the question is worded. As such, it is an inappropriate answer. Remember, the order of the words in the answer must appear in the same way as the question. Considering the other choices, "human is to mammal" has a categorical relationship in which humans are a type of mammal. "Spark is to fire" holds a cause and effect relationship and "ugly is to hideous" represents an increase in degree.

An engine is a part of an airplane. Likewise, a window is a part of a wall, making the choice "wall" the best answer. The choice "glass" would make the relationship whole to part or characteristic of, as you can think of glass as being a part of a window or describing one type of window. A "window" is an opening in a wall and does not necessarily need to have glass in it, though it usually does. Another word for "drapes" is "curtains," both of which cover a window. "Clear" is another characteristic of a glass window. "Wood" is unrelated unless you consider that a frame for a window may be made out of wood. In that case the relationship would be whole to part.

The relationship of these words is a part to a whole. More accurately, it is an outermost part and what it connects to in the human body or a tree. A "finger" connects to a "hand," and a "leaf" connects to a "twig."

“Link” is a word that when used as a noun, can mean a ring that helps to make up a chain, so a link is the individual unit that makes up a chain, and we need to pick out an answer choice in which the first word is the individual unit that makes up the second word. “Hilt is to sword” and “handle is to bag” may each look like a potentially correct answer, but because swords are made of more than hilts and bags more than handles, neither answer can be the correct one. “Metal is to armor” and “stitch is to fabric” may both look like appealing answer choices because metal makes up armor and stitches make up fabric, but because “stitch” is a repeated unit that makes up fabric whereas “metal” just describes the substance that armor is often made of (and is not a repeating unit), “stitch is to fabric” is the correct answer.

Since a pillowcase covers the outside of a pillow, we need to pick out a word which represents what covers the outside of an orange. Since we are considering "orange" as a tangible object—the fruit, not the color—we can ignore "blue," and since "citrus" is an adjective, we need not consider it either. Between "rind," "leaf," and "tree," "rind" is the best answer, since it can mean a fruit's tough exterior skin.