A company manufacturing computer chips finds that 8% of all chips manufactured are defective. Management is concerned that high employee turnover is partially responsible for the high defect rate. In an effort to decrease the percentage of defective chips, management decides to provide additional training to those employees hired within the last year. After training was implemented, a sample of 450 chips revealed only 27 defects. Was the additional training effective in lowering the defect rate? Which of the following statements is true about this hypothesis test?

a		It is a two-tailed test about a proportion.
b		It is a one-tailed test about a mean.
c		It is a one-tailed test about a proportion.
d		It is a two-tailed test about a mean.