Science quiz question 2, Thanks if you help!

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds

the answer is sex-linked recessive.

sound moves fastest in solids because the molecules are tightly packed and it allows sound to vibrate

if someone had the list of traits you provided