What is the arrangement of paired chromosomes referred to as?

The correct term for the arrangement of paired chromosomes is "karyotype." A karyotype is a visual profile of all the chromosomes in a cell, typically organized into pairs based on their size, shape, and number. This arrangement is essential for genetic analysis, as it allows researchers to detect chromosomal abnormalities, assess the genetic composition of an organism, and understand inheritance patterns.

The other terms provided have different meanings. For example, "phenotype" refers to the observable physical and physiological traits of an organism, which arise from the expression of its genes, rather than the arrangement of chromosomes. "Genotype" pertains to the genetic makeup of an organism, denoting the specific alleles present, but does not illustrate how those chromosomes are arranged. "Chromatography" is a laboratory technique used for separating mixtures, often in chemical contexts, and is unrelated to genetics or chromosome arrangement.