Let \( A_1,B_1,C_1 \) be three points in the \( xy \)-plane. Suppose that the lines \( A_1C_1 \) and \( B_1C_1 \) are tangents to the curve \( y^2=8x \) at \( A_1 \) and \( B_1 \), respectively. If \( O=(0,0) \) and \( C_1=(-4,0) \), then which of the following statements is (are) TRUE?
