To specialize in a cosmetology service, one must undergo additional training and develop specific expertise. This training is crucial for mastering advanced techniques in areas like hair, skin, or nail care. Other skills, while useful, do not directly relate to the specialization process. ;
Becoming a specialist in a cosmetology service requires additional training and expertise in that specific area. This training helps in mastering techniques relevant to services such as hair styling or skincare. Therefore, the correct answer is (A) additional training and expertise.
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