Which of the following is a technique for developing vocal abilities?

Breath control exercises are fundamental for developing vocal abilities as they directly impact the quality and sustainability of a singer's voice. Proper breath control helps singers manage their airflow, which is essential for producing a steady tone and maintaining vocal stability. It allows for longer phrases, greater dynamic range, and better vocal health by reducing the strain on the vocal cords. Techniques often include diaphragmatic breathing, sustained vowel exercises, and various warm-up exercises designed to increase lung capacity and control.

The other options, while important in the context of music and performance, do not directly focus on enhancing vocal techniques. Using an electronic tuner is primarily a tool for pitch accuracy, which does not improve vocal abilities alone. Playing a piano is beneficial for accompanying and understanding musical structure but does not develop the physiological aspects of singing. Reading music notation is crucial for learning and interpreting music, but it does not contribute to the physical techniques needed for effective vocal performance.