Question

Select the sentence that correctly uses commas in a non-restrictive phrase. A river, that is polluted, is unsafe for swimming. Polluted rivers, which can exist anywhere, are unsafe for swimming. When a river becomes polluted, it is no longer safe for swimming. However, rivers sometimes become polluted when nearby farms use too many poisons.

Answer 1

However, rivers sometimes become polluted when nearby farms use too many poisons.  i believe it is that one