The bond between one carbon atom and one oxygen atom is polar but due to the fact that there is another oxygen attached to the carbon which has the same electronegativity value as the oxygen on the other side, the effect of polarity is canceled.

is non-polar because the oxygens symmetrically alligned on the opposite sides of the carbon cancel the polarity effect.
The type of solution researchers should use to cause blood cells to lyse (burst) would be a hypoosmotic solution. It is a solution which has lesser solute concentration in relation with another solution. For instance, a cell of a fish from fresh water would be hypoosmotic to salt water.
Im pretty sure your answer is b.
Sams drink was colder therefore didn’t melt the sugar like the hot coffee did so C)