In curtate life expectancy, ex_(curtate) relates to survival probability p_x and the life expectancy at age x+1 by which expression?

• A. p_x (1 + e_{x+1})
• B. e_x = p_x e_{x+1}
• C. e_x(curtate) = p_x / (1 + e_{x+1})
• D. e_x = p_x + e_{x+1}

Answer: (A)