"Convince" and "persuade" are synonyms of one another. Both words mean to cause someone to do something they originally did not want to do. So, to solve this analogy you need to figure out which of these is a synonym of "bite." The correct answer is "nibble." Usually "nibble" means to take a small bite or to bite gently.

"Heartfelt" and "sincere" both mean honest and open, free from lies and tricks. These two words are "synonyms" of one another because they have the same meaning. So, which of these words is a synonym of "bare?" Well, "bare" means empty, lacking features, naked. The best available synonym is therefore "barren" which means not having anything, empty, lacking life. Additionally, "unkempt" means messy, untidy; "youthful" means young.

"Flex" and "bend" are synonyms of one another, both words mean to stretch or twist one's body. So, to solve this analogy you need to figure out which of these is a synonym of "impede." Well, "impede" means block the path of, get in the way of. This is the same definition as "obstruct," so this is the correct answer. Additionally, "postpone" means delay, stop with the intention to start again later; "irritate" means annoy; "glance" means look at quickly and secretively; "mourn" means feel or express sadness about the loss of.

"Contempt" means dislike for and "respect" means admiration for, like for. These two words are considered "antonyms" because they have opposite meanings. To solve this analogy you therefore need to figure out which of these words has the opposite meaning to "worst." The correct answer is "optimum" which means best, perfect. All the other answer choices are related to being "worse" or "worst."

Since "cold" and "hot" are opposites, we're looking for an answer choice in which the two words are opposites. Since "day" is the opposite of "night," "day is to night" is the correct answer.

Both sets of words are antonyms.  

Both sets of words are antonyms. 

Both of the sets are antonyms.  

Since "hungry" and "full" are opposites, we need to pick out another pair of words which are also opposites. Since "exhausted" ("very tired") is an opposite of "energetic," "exhausted is to energetic" is the correct answer.

"Welcome," when used as an adjective, means "of a guest or new arrival: gladly received," and "excluded" is an adjective that means "deny (someone) access to or bar (someone) from a place, group, or privilege," so the two words are antonyms. That means that we need to pick out an answer choice that consists of two antonyms. "Ready" cannot be the correct answer, then, because "ready" is a synonym, not an antonym, of "prepared." "Unready," however, is an antonym of "prepared," just like "welcome" is an antonym of "excluded," so "unready" is the correct answer.