Below Freezing and Above Boiling, Cells Are Unable to Function

Multiple Choice

Below freezing and above boiling, cells are unable to function as "liquid machinery." However, most organisms' cells are still limited from functioning throughout this full range of liquid temperatures. At the molecular level in different organisms, cells' ability to vary in their tolerance to temperature, etc., is most closely related to variation in

A) enzyme activity and protein denaturation.
B) ATP efficiency.
C) ability to form glucose polymers.
D) replication of nucleic acids.
E) extent of saturation of fatty acids.