The instructions for the genetic traits of an organism are directly determined by the

B: sequence of the bases in DNA molecules

Explanation:

Complete Question:

The instructions for the genetic traits of an organism are directly determined by the

A: numbers of A, T, C and G units in a sugar molecule

B: sequence of the bases in DNA molecules

C: length of a DNA molecules

D: way the bases are paired in the two strands of a DNA molecule

The instructions for the genetic traits of an organism are directly determined by the sequence of the bases in DNA molecules.

DNA is the molecule that carries the genetic information and these instructions for the genetic traits or characteristics of an organism are directly determined by the arrangement of the four type of molecular bases (adenine, thymine, guanine, and cytosine) in the deoxyribonucleic acid.

Answer: DNA