Which from following statements regarding biological importance of...

Which from following statements regarding biological importance of elements is NOT true?

Options

A $\text{Ca}^{2+}$ ions are required for contraction and stretching of muscles.
B $\text{Mg}^{2+}$ ions are important for breaking of glucose and fats in protein synthesis.
C $\textK^{+}$ ions are most abundant in extra cellular fluid.
D $\text{Na}^{+}$ ions regulate water flow across the membrane.

C. $\textK^{+}$ ions are most abundant in extra cellular fluid.

Sodium ions (

\text{Na}^{+}

) are the most abundant cations in the extracellular fluid (blood plasma and interstitial fluid), whereas potassium ions (

\textK^{+}

) are the most abundant cations in the intracellular fluid (within cell fluids).

Therefore, the statement that

\textK^{+}

ions are most abundant in extracellular fluid is incorrect.

Answer:

\textK^{+}

ions are most abundant in extra cellular fluid.