The writer comments on Stem's investigation and analysis in a ______ tone.

A．Those who criticize Stern would be wrong in effect.
B．Stem's analysis of terrorist structures is quite convincing.
C．Stern does not try to offer solutions to end terrorism.
D．Humus uses selective readings of history to justify violenc

A．moving into the grocery business
B．squeezing its labor costs
C．entering into anti-union activities
D．employing illegal workers