Question

there are over 150 species of the cactus genus mammillaria throughout the americas, but their survival can be threatened by high precipitation and dense vegetation that blocks sunlight. researchers have located species from the genus in almost every state in mexico, with several of them, like m. knippeliana, restricted to only one state. the fact that this genus has not been observed in eastern and western coahuila has been attributed to a lack of appropriate habitat, but much of the landscape in this area is notoriously inaccessible, which suggests that. which choice most logically completes the text? a m. knippeliana may have been overlooked in eastern and western coahuila because of its similarity to another species. b the current methods of collecting and tracking mammillaria species throughout mexico may cause an overestimation of the number of species in this genus. c the perceived absence of mammillaria in eastern and western coahuila may be due to insufficient exploration of the region. d the dense vegetation and high annual precipitation levels in eastern and western coahuila impede the ability of mammillaria species to survive.

Explanation:

The text mentions that the genus Mammillaria has not been observed in eastern and western Coahuila, and attributes it to a lack of appropriate habitat. It also notes that the landscape in this area is notoriously inaccessible. Option C is correct as it suggests that insufficient exploration of the region in Coahuila may account for the perceived absence of Mammillaria in eastern and western Coahuila. Option A is incorrect as there is no mention of similarity - related oversight for M. knippeliana. Option B has no basis in the text regarding over - estimation due to collection methods. Option D is wrong as the text does not indicate that vegetation and precipitation impede survival of Mammillaria species in Coahuila.

Answer:

C. the perceived absence of Mammillaria in eastern and western Coahuila may be due to insufficient exploration of the region.