Frown is to smile as strength is to what?

The relationship between the words "frown" and "smile" is one of opposites or contrasting states; a frown represents a facial expression associated with sadness or displeasure, whereas a smile signifies happiness or joy. To find a word that pairs with "strength" in a similar manner, it is essential to understand what opposite or contrasting state can be related to it.

Among the options provided, "rest" is the most fitting choice as it implies a state of relaxation or reduction in physical exertion, which can be seen as a contrast to "strength," which implies power, energy, and active engagement. In this context, rest can be viewed as a reduction in strength or energy, just as a frown is the negative counterpart to a smile.

The other options do not align with this oppositional relationship: they represent actions or states that do not inherently contrast with strength in the same way that rest does. Therefore, "rest" is the most suitable answer that mirrors the relationship of opposites as seen with "frown" and "smile."