What taste is commonly associated with strongly alkaline waters?

Strongly alkaline waters are typically associated with a bitter taste. The alkaline minerals, such as calcium, magnesium, and sodium, can lead to this flavor profile, especially when their concentrations are high. This bitterness is a result of the chemical properties of these minerals interacting with the taste receptors on the tongue.

In contrast, while the choices of salty or metallic can be associated with various mineral contents or dissolved solids, they do not specifically represent the taste profile commonly linked to alkaline waters. Soda, which is often perceived as sweet and carbonated, does not accurately reflect the characteristics of alkaline water either, as such waters do not possess a soda-like taste. Therefore, the correct association for strongly alkaline waters is indeed a bitter taste.