Concept:Sunnah steps of ablution include recommended actions performed in addition to the obligatory (Fard) acts of wudhu.
They enhance the reward and completeness of the ablution.
Explanation:Among the known Sunnah acts during ablution are rinsing the mouth, sniffing water into the nose and blowing it out, and wiping the two ears.
Another well-established Sunnah is cleaning the teeth with a miswak or a toothbrush before beginning wudhu.
Therefore, the act that best fits the list in the question is brushing the teeth.
Wiping the head again from the back of the skull is not a separate Sunnah step.
Supplication at every stage and saying the du'a aloud are not prescribed Sunnah steps of wudhu.
Answer:C. brushing the teeth.