Which of the following statements is TRUE（）

A. When a rating agency downgrades a security, the bond’s price usually falls.

B. Technical default usually refers to the issuer’s failure to make interest or principal payments as scheduled in the indenture.

C. Default risk is important because if a bond issuer defaults, the bondholder likely loses his entire investment.

影响大学生心理健康的首要因素是（）

A、生物遗传

B、学校环境

C、家庭环境

D、负面生活事件

E、社会环境