Answer: C) ABAB.
Explanation: When we want to determinate the rhyme scheme in a poem or a stanza, we need to pay attention to the final syllable of each line, and the ones that have the same sound, we classify them with a letter (starting with "A" in the first line). In the given poem, the lines 1 and 3 end with the words "six" and "bricks" which have same sound (letter A) and the lines 2 and 4 end with the words "house" and "mouse" which also have the same sound (letter B). So the rhyme scheme would be: ABAB.
