Competitive threats to the profitability or financial stability of a firm are best categorized as an accounting fraud risk factor related to:（）

A. opportunities.

B. incentives and pressures.

C. attitudes and rationalizations.

我国法定传染病中甲类传染病包括

A．天花和鼠疫

B．狂犬病和天花

C．霍乱和副霍乱

D．鼠疫和霍乱

E．艾滋病和霍乱