Question

semipermeable means...
only some things can get through.
nothing can get through.
only water can get through.
everything can get through.

Explanation:

A semipermeable membrane allows only certain substances (usually small molecules like water, some ions) to pass through while restricting others (like large molecules). "Only some things can get through" aligns with this definition. "Nothing can get through" is impermeable. "Only water can get through" is too restrictive as some other small entities might pass. "Everything can get through" is fully permeable.

Answer:

only some things can get through.