Question

floppy ears are an example of...
a phenotype.
a genotype.
a chromosome.
a karyotype.

Explanation:

A phenotype is the observable physical or biochemical characteristics of an organism, resulting from the interaction of its genotype (genetic makeup) with the environment. Floppy ears are a visible trait, thus fitting the definition of a phenotype. A genotype refers to the genetic information (genes) an organism has, not the visible trait itself. A chromosome is a structure within cells that contains DNA (genetic material). A karyotype is a complete set of chromosomes in an organism, usually presented as a micrograph image arranged in a standard format.

Answer:

a phenotype.