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.

“Splinter” is a word that when used as a noun means a tiny, sharp piece of wood or glass. So, a splinter is a small piece of wood, and we need to pick out an answer choice that conveys the material that a shard can be made of. While “glass,” “wool,” and “leather” may each look like a potentially correct answer choice, because each refers to a tangible material, “shard” is defined as a small piece of broken glass or ceramic with sharp edges, and because “glass” is the only material mentioned in the definition of “shard,” “glass” is the correct answer.

“Core” can be used as a noun that means the tough part of a fruit found at its center, and apples have cores at their centers which people do not typically eat. So, we need to pick out an answer choice that describes a part of a peach which people do not eat, particularly one found in the center of a peach. While “pit” and “rind” may each look like a potentially correct answer, “rind” is a noun that means a fruit's tough exterior skin, but because peaches don’t have rinds, “rind” cannot be the correct answer. “Pit,” however, when used as a noun, can mean a fruit's stone, and because peaches contain pits just as apples contain cores, “pit” is the correct answer.

A "thesis" is part of an "essay," so to solve this analogy, you have to determine which of these answer choices includes an "engine" as one of its parts. The correct answer is a "car."

A bishop is a ranking member of the church, so to solve this analogy, you have to determine which of these answer choices is an organization that includes barons amongst its members. The correct answer is “aristocracy,” which is the name given to an entrenched upper class system, like the royalty or nobility in England. For clarification, "oligarchy" is the name of the government ruled by a few, and "tenure" is the status of guaranteed employment achieved by faculty members, usually after a number of years.

“Symptom” is a noun that means an effect characteristic of a disease, so a doctor might consider a patient’s symptoms in order to figure out what disease the patient has. We need to pick out an answer choice that describes what a clue might help a person figure out. While “mystery” and “hint” might each look like a potentially correct answer, “hint” is a synonym of “clue,” not something a clue might help one figure out, so “hint” cannot be the correct answer. A clue might help someone figure out a mystery, however, just as a symptom might help a doctor figure out what disease a patient has, so “mystery” is the correct answer.

The relationship in "puzzle is to piece" is whole to part. The best choice is "cushion," as a cushion is a part of a couch. Both "brown" and "comfy" are possible characteristics of couches. The choice "seat" would make the relationship categorical because a couch is a type of seat. The choice "drawer" is unrelated to the word "couch."

A group of wolves is called a pack. Similarly, a group of geese is called a gaggle. 

None of the other analogies have this specific relationship.

Groups of children are not called a school, although groups of children do go to school.

Wolf and dog are related, but the analogy does not fit the relationship of single animal to group of that animal.

Groups of pigs do live on farms, but the order of the words is incorrect: a group of farms is not called a pig.

A group of reptiles is not called a herd; a herd typically refers to a group of hoofed animals.