Some people use genetic testing before becoming pregnant to find out whether a. their child is likely to be tall. b. their child is likely to have dawn syndrome. c. they’re carriers of a genetic disorder. d. they’re able to become pregnant

C. They're carriers of a genetic disorder.

Genetic testing can help screen for variants/mutations in potential parents' DNA. If one or both parents test negative, they will know their child will not inherit the disorder. Likewise, if they both are carriers, there is a chance their child could be affected, which is helpful information in determining whether to have their own children, or how to address their child's possible disorder.

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.