The right answer is "There are fourteen lines with five sets of stressed and unstressed syllables. "
Explanation: Iambic pentameter is a type of metric that is used in poetry and drama. It describes a certain rhythm that words establish in each verse. This rhythm is measured in small groups of syllables; these small groups are called "foot." The word iambic describes the type of foot that is used. The word pentameter indicates that a verse has five feet. In English, rhythm is created through the use of tonicity, alternating between tonic and non-tonic syllables. An anglophone non-tonic syllable is equivalent to a classic short syllable, whereas an anglophone tonic syllable is equivalent to a classic long syllable.
Iambic pentameter is, therefore, a verse composed of five pairs of short / long syllables, or atonic / tonic syllables. If the short / long or atonic / tonic pattern were to be reversed, producing a five-pair long / short verse, or unstressed tonic / atonic, this verse would be described as an example of exchangeable pentameter