Alliteration

Can you recall the definition of alliteration by looking at the underlined hints in the stanza below?

There is no clutter cluttered up
more closely, I presume,
than the clutter clustered clingingly
in my friend, Betty's room.

(from the poem "Betty's Room" in A Little Bit of Nonsense by Denise Rodgers)

Watch the video to learn more about alliteration: