The following paragraph does not have "unity" because there is one sentence that doesn't directly support the topic sentence. The sentence that does not directly support the topic sentence is

$($a$)$ Later in the dusky streets I walked among the Navajo camps, past the doomays of the town, from which came the good smells of cooking, the festive sounds of music, laughter, and talk. $($b$)$ The campfires rippled in the crisp wind that arose with evening and set a soft yellow glow on the ground, low on the adobe walls. $($c$)$ A natural building material used for several thousand years, adobe is composed of sand and straw, which is shaped into bricks on wooden frames and dried in the sun. $($d$)$ Mutton sizzled and smoked above the fres: fat dripped into the flames; there were great black pots of strong coffee and buckets full of fried bread; dogs crouched on the rim of the light, the many circles of light; and old men sat hunched in their blankets on the ground, in the cold shadows, smoking. $($e$)$ Long into the night the fres cast a glare over the town, and I could hear the singing, until it seemed that one by one the volces fell away. and one remained, and then there was none.

$($Momaday $1976).$