Consider the following two statements about putable bonds: Statement 1: As yields rise, the price of putable bonds will fall less quickly than similar option-free bonds (beyond a critical point) due to the increase in value of the embedded put option. Statement 2: As yields fall, the price of putable bonds will rise more quickly than similar option-free bonds (beyond a critical point) due to the increase in value of the embedded put option. Are these statements correct or incorrect（）

A. Statement 1 is correct and Statement 2 is incorrect. 

B. Both statements are incorrect. 

C. Statement 1 is incorrect and Statement 2 is correct.

在设计重力式挡土墙时，土对挡土墙墙背的摩擦角δ除了与墙背填土的性质与排水条件有关以外，还与( )因素有关。

A．墙背倾角

B．墙背粗糙程度

C．挡土墙高度

D．作用在墙背上土压力的大小