The ________ stage of prenatal development takes place during the first two weeks after conception

Which of the following statements about public policies for older adults in the United States is true?

A) During the 1960s, U.S. federal spending on programs for older adults was greatly expanded. B) Social security and Medicare consume about half of the federal budget for older adults. C) All Americans over age 65 are guaranteed a minimum income greater than the poverty level. D) Social Security benefits are usually enough to serve as the sole source of retirement income.

According to the concept of __________, our genes influence the environments to which we are exposed

A) canalization B) gene–environment correlation C) heritability estimation D) natural selection