How do the nitrogen bases pair together in DNA?

What feature of cell theory is best demonstrated in the image

How does the molecular clock work? a. it analyzes the brain functionality of two different species.b. it examines and compares the physical characteristics of two different species.c. it illustrates relationships between two different species.d. it compares the number of mutations that exist in the dna of two different species.

Why does bubbling occur when vinegar mixed with baking soda