Potassium (K) and copper (Cu) are both in period 4. They both have .

A: four electron shells
B: similar properties
C: the same number of electrons
D: the same number of protons

A): four electron shells

Explanation:

In the period table, atoms are arranged in rows called periods and columns called groups. The arrangement of atoms in groups is based on the number of their valence electrons while the arrangement of atoms across the periods is based on their number of electrons shells. Atoms are arranged across the periods in increasing order of their atomic number i.e., according to their number of electrons. Potassium has 19 electrons while copper has 29 electrons. Both has four electrons shells according to their electronic configuration.

an organism's phenotype is the  form of a trait  that it  displays. for  flowercolor, a pea  plant  can  display  a phenotype of purple or white flowers. an organism's  genotype  is the alleles of a gene it contains. based on his data, mendel concluded that a phenotype can be  determined  by more than one  genotype.

c should be the answer