If You Add Togavirus Virions to Host Cells and Then

If you add togavirus virions to host cells and then lower the pH of the medium, what will happen?

A) The virions will become inactivated.
B) The virus will bind more tightly to the host cell receptor.
C) The virions will fuse to the plasma membrane of the cell.
D) The virus will be released from the host cell receptor.
E) The virions will be taken up by receptor mediated endocytosis.