Which of the Following Is an Example of a Primary $\mathrm{Na}^{+}$

Multiple Choice

Which of the following is an example of a primary active transport process?

A) $\mathrm{Na}^{+}$ -glucose transport in small intestinal epithelial cells
B) $\mathrm{Na}^{+}$ -alanine transport in renal proximal tubular cells
C) Insulin-dependent glucose transport in muscle cells
D) $\mathrm{H}^{+}-\mathrm{K}^{+}$ transport in gastric parietal cells
E) $\mathrm{Na}^{+}-\mathrm{Ca}^{2+}$ exchange in nerve cells