Answer:
First you have to think of the most challenging thing youve ever done, here is a sentence starter: The most challenging thing i have ever done was...
Explanation: Example the most challenging thing i have ever done was when i ran in a had to overcome my fear of snakes.
Answer:
Vertebrates are members of the kingdom Animalia and the phylum Chordata . Recall that animals that possess bilateral symmetry can be divided into two groups—protostomes and deuterostomes—based on their patterns of embryonic development. The deuterostomes, whose name translates as “second mouth,” consist of two major phyla: Echinodermata and Chordata. Echinoderms are invertebrate marine animals that have pentaradial symmetry and a spiny body covering, a group that includes sea stars, sea urchins, and sea cucumbers. The most conspicuous and familiar members of Chordata are vertebrates, but this phylum also includes two groups of invertebrate chordates.
Deuterostome phylogeny. All chordates are deuterostomes possessing a notochord at some stage of their life cycle.
Explanation:
I would say that it depends on the audience. Personally, a debate regarding ethics and moral dilemma is interesting. Read The Fat Man and the Impending Doom. It's just one paragraph so it's not going to bore audience.
https://thedailydilemma.wordpress.com/2007/06/18/fat-man/
I believe that this type is a lecture-forum discussion.
"What was the best holiday ever for you?" might work