A researcher wants to know if the association between education and life expectancy varies by gender. Which is the simplest regression that can help answer this question?
A. LifeExpectancy = B0 + B1*female + E
B. LifeExpectancy = B0 + B1*educ+ E
C. LifeExpectancy = B0 + B1female + B2Educ + E
D. LifeExpectancy = B0 + B1female + B2Educ + B3femaleeduc + E
Answer: D. LifeExpectancy = B0 + B1female + B2Educ + B3femaleeduc + E