Why do elements that are in the same group of the periodic table share similar properties? A. They all have the same number of electrons in the outer shell.
B. They all have the same atomic mass.
C. They are all metals.
D. They are all very reactive with other elements.

Choose the best definition of allele. a. one of several possible versions of a gene, which each produce a different phenotype b. an organism that's purebred for a given trait c. the process of fertilizing a plant with pollen from another plant d. a set of genes that are located on the same chromosome and so are tightly linked