Chapter 5, Problem 4RA

The conversion of lactic acid to pyruvic acid occurs

$\begin{array}{l}\text{a}\text{. in anaerobic respiration}\text{.}\\ \text{b}\text{. in the heart, where lactic acid is aerobically respired}\text{.}\\ \text{c}\text{. in the liver, where lactic acid can be converted to glucose}\text{.}\\ \text{d}\text{. in both }a\text{ and }b.\\ \text{e}\text{. in both }b\text{ and }c.\end{array}$