Which of the following best states the principle of homogeneity of dimensions in a physical equation?
a) The dimensions of the left-hand side and right-hand side need match, but the dimensions of individual terms within each side may differ.
b) All terms in a physical equation must have identical units even if their dimensions differ.
c) Each term in a physically meaningful equation must have identical dimensions.
d) A physical equation is valid provided any dimensional differences are compensated by suitable numerical constants.