Select the most appropriate option to fill in the blanks.
Sugar ________ in water because it is made up of molecules of sucrose, a compound held together by relatively weak bonds. When the sucrose molecules mix with water, the water molecules ________ and break the bonds holding together the sugar molecule.

Let's analyze the context of the sentence:
The first blank describes what happens to sugar when mixed with water. While sugar "dissolves," in common parlance or descriptive texts, terms like melts or disappear might be used conceptually, though scientifically it dissolves. Looking at Option A, melts fits the initial blank conceptually, and surround perfectly describes how water molecules interact with sucrose molecules (solvation/hydration layer) to break their chemical bonds.

Options B, C, and D contain words like "limit", "grid", and "edge" for the second blank, which do not fit the actions of water molecules breaking chemical bonds.

Thus, Option A provides the most appropriate contextual fit.