What is the difference between participles and gerunds

Participles:

Always function as adjectives, adding description to the sentence.If the participle is present, it will dependably end in -ing.A regular past participle will end in a consistent -ed.

  Examples:

"The horse trotting up to the fence hopes that you have an apple or carrot.""The water drained slowly in the pipe clogged with dog hair"

Gerunds:

Always function as nouns, so they will be subjects, subject complements, or objects in the the sentence.CANNOT be a verbEnds in -ing.

  Examples:

"Lily hates waking up to the buzz of the alarm clock.""While we were walking on the beach, CJ jumped over the jellyfish that had washed ashore."

The answer would be b.

I’m going to guess #4 since that seems pretty logical.