Wegener believed continents moved, but he did not know how. Identify what needed to happen before Wegener's idea about moving continents could be proven.(1 point) Advances in technology were needed to gather more evidence.

Wegener had to recheck his data and change his conclusions.

Scientists had to directly observe tectonic plate movement.

New information was needed on the composition of Earth's crust.

Embryonic stem cells are cells derived from an embryo. these cells can be used to create new tissues for patients suffering from certain illnesses and disorders. which statement best summarizes why the use of embryonic stem cells could be seen as unethical? a. some people consider embryos to possess rights equal to those of fully developed human beings. b. extracting stem cells from embryos is a very energy-intensive process, which consumes resources that could be used elsewhere. c. embryos are difficult to obtain, so the monetary cost of using them for research outweighs their benefit. d. the process of extracting stem cells from embryos generates biohazardous waste that cannot be safely disposed of.