The term refers to an increase in body size without overall shape change.

Growth

Explanation:

The growth of the organism is said to take place when it grows in size however during this growth phase there is no change in the shape of the organism. 

During the growth of the organism, there is an increase in size and mass and this takes place in both unicellular and multicellular organisms. 

In unicellular organisms, the growth takes place in the form of an increase in cellular content and the growth in multicellular organisms takes place by an increase in the number of cells. 

the answer is b.) hydrogen bonds between bases.