Which of the Following Statements About Minerals in Soil Is

Multiple Choice

Which of the following statements about minerals in soil is true?

A) There are only two mineral ions, potassium and magnesium, that are essential for plant growth.
B) Negatively charged mineral ions are often washed out of the root zone.
C) Clay minerals are usually positively charged.
D) Clay minerals very rarely have charged ions
E) Clay particles may "hold" mineral ions in the soil and prevent their use by plants.