Which of the following describes "bilabial" sounds?

"Bilabial" sounds are specifically produced using both lips. This involves articulations where both the upper and lower lips come together to create sounds. Examples of bilabial consonants in English include the sounds represented by the letters "p," "b," and "m." These sounds are formed by pressing the lips together and then either releasing them or allowing air to pass through them while vibrating the vocal cords, depending on whether the sound is voiceless (like "p") or voiced (like "b" and "m").

The other options refer to different articulatory features. Sounds produced with the back of the throat refer to uvular or pharyngeal sounds, which involve the back of the tongue. Sounds that require the tongue encompass various sound categories such as alveolar and palatal sounds, while sounds produced with the teeth are typically dental sounds. None of these describe bilabial sounds accurately, hence reinforcing that the correct choice is the one that highlights the use of both lips.