Which of the Following Accurately Describes Why Specific Material Uses

Which of the following accurately describes why specific material uses a protein to cross the membrane?

A) The hydrophobic core of a membrane will only allow hydrophobic (i.e. ,non-polar) substances to cross without a membrane protein.
B) The hydrophilic core of a membrane will only allow hydrophilic (i.e. ,polar) substance to cross without a membrane protein.
C) The membrane will allow any substance to cross it as long as it moves from a high concentration to low.
D) The membrane will allow any substance to cross it if the concentration of solute is high enough on one side of the membrane.
E) Material can only cross the membrane via a protein.