President Bush has once again started speaking out for comprehensive immigration reform, a

nd a draft plan to rally Republican senators on the issue is circulating just as Congressional hearings on the issue approach. Members of Congress recognize that voters are looking for real reform. that rests on resolute, effective enforcement of our immigration laws.

The only serious legislative proposal on the table offers such enforcement, because it focuses on making employers accountable for their hiring practices. To that end, the bill incorporates lessons learned from the largest immigration enforcement operation ever undertaken. Last December, Department of Homeland Security agents descended on meat processing plants run by Swirl & Company in six states, arresting more than 1,200 unauthorized workers.

The arrests were astonishing because Swift participates in Basic Pilot, a voluntary Department of Homeland Security program that allows employers to electronically verify the work eligibility of newly hired workers against department and Social Security databases. The program is seen as the precursor for a verification system that would become mandatory with comprehensive immigration reform. Since Swirl was using the department's system, how did it end up with illegal workers？

The Basic Pilot program has a fatal flaw, which is that it requires only electronic verification of employment qualification. An effective program should also insist on tamper-proof identification documents for job-seekers, incorporating biometrics like digital photographs and fingerprints to prove identity. Only then would it be possible to establish not only that job applicants are authorized to work, but also that they are who they say they are. Otherwise, valid Social Security numbers can be presented to employers, and Basic Pilot will verify them, but the numbers may not belong to the workers who present them.

To insist on secure documents with biometric identifiers is not a call for a national ID. Green cards, temporary work permits and passports are secure and reliable for hiring purposes. Adding Social Security cards to this list, establishing a single standard for their security features, and replacing old cards over a designated period would resolve the problem on a national scale.

Only then would employers be able to comply reliably with verification requirements as the basis for sound enforcement and, by extension, border control. Legal immigrants and American citizens could prove their identities and qualifications to work without facing discrimination based on appearance or language. Scarce enforcement resources could be spent on apprehending real criminals and addressing national security threats. And a new system of enforcement would at last have a chance to win back public confidence in the nation's immigration policies. After more than 20 years of failed efforts, Congress must not bake half a loaf. Secure biometric Social Security cards are an essential ingredient in any comprehensive immigration reform.

The case of Swirl unauthorized workers was caused possibly because ______

A．the company has no identity verification measures on their workers.

B．the employers of the company are not accountable for their employment practices.

C．the lack of biometric identifier in its identity verification system.

D．it meant to break the legislation proposal on immigration problems.