Which word does NOT belong with the others?

A leopard, cougar, and lion all belong to the cat family; an elephant does not.

The yarn, twine, and cord are all used for tying. The tape is not used in the same way.

Heading, body, and closing are all parts of a letter; the letter is the whole, not a part.

Freeway, interstate, and expressway are all high- speed highways; a street is for low-speed traffic.

A branch, leaf, and root are all parts of a tree. The dirt underneath is not a part of the tree.

The cornea, retina, and pupil are all parts of the eye.

The noun, preposition, and adverb are classes of words that make up a sentence. Punctuation belongs in a sentence, but punctuation is not a class of word.

An index, glossary, and chapter are all parts of a book. Choice a does not belong because the book is the whole, not a part.

The first three choices are all synonyms.

An odometer is an instrument used to measure mileage. A compass is an instrument used to determine direction. Choices a, b, and c are incorrect because none is an instrument.