A couple wants a second child that is biologically related to them. They have been trying for five years. The wife is 45 years old and healthy, with no history of sexually transmitted diseases. Three rounds of artificial insemination with her husband's sperm have failed. There is no evidence of any problem with her husband's sperm count or motility. What would be the most likely next step

Ascientist is investigating the effects of salinity on fish development. he places fertilized fish eggs in an aquarium that contains low salinity and observes their development. what factor would improve experimental design the most? place the fish eggs in the open ocean because that is the natural habitat include another aquarium that has normal salinity to compare to the low salinity aquarium include an aquarium that replaces salt with sugar to confirm that the effects are specific to salt grow algae with the fish eggs in order to provide adequate nutrients to the developing embryos