The answer to your question is: the third option is correct.
Explanation:
"Alkenes" ________.
are reasonably soluble in water This option is incorrect, alkenes are insoluble in water.
are relatively polar compounds This option is wrong, alkenes are not polar molecules.
have lower boiling points than alcohols of similar molecular weight This option is true, alkenes have a lower boiling point than alcohols.
both have lower boiling points than alcohols of similar molecular weight and are relatively polar compounds. This option is incorrect because is combining true with false facts.
