On the periodic table there are columns that go up and down. elements that are in the same column

a) tend to have properties that are different
b) tend to have properties that are similar
c) tend to have similar atomic mass
d) tend to have different numbers of valence electrons

i think the answer is b

similar properties

specific gravity is the density of a substance divided by the density of water. since (at standard temperature and pressure) water has a density of 1 gram/cm3, and since all of the units cancel, specific gravity is usually very close to the same value as density

so "c" is the answer

plz give brainliest