Final answer:
Nasalance increases as nasal intensity increases relative to oral intensity.
Step-by-step explanation:
Nasalance is a measure of the amount of nasal sound in a person's speech. The product of nasalance increases as nasal intensity increases relative to oral intensity. Therefore, the correct answer is a. Increases - increases. When more air is passing through the nasal cavity, the nasalance increases, indicating a higher nasal intensity compared to oral intensity.