When an employer is charged under Section 8(a)(3 ) for refusing to hire an applicant whom the ...

When an employer is charged under Section 8(a)(3 ) for refusing to hire an applicant whom the employer suspects to be a union organizer, which of the following can the employer use to defend his decision?
 A) By raising a reasonable question as to the applicant's actual interest in working for the employer
 B) By citing the employers' rights as defined in Section 7 of the NLRA to defend against the labor practice
 C) By citing the closed shop agreements in place in the firm
 D) By agreeing to establish and administer in-house unions