The correct answer is option 3. Bitter.
The taste of a substance is a sensory perception, and while it's not recommended to taste chemicals due to safety reasons, the taste of bases is generally described as bitter. This characteristic taste is a result of the interaction of bases with taste receptors on the tongue.
Bases, or alkaline substances, typically have a bitter taste when they come into contact with the taste buds. Some common examples of bases that exhibit a bitter taste include sodium hydroxide (NaOH) and potassium hydroxide (KOH). These substances are found in various cleaning products, so it's essential to exercise caution and avoid tasting them.
The bitter taste of bases is one of the sensory properties used to identify and categorize substances, but it's crucial to rely on more reliable methods, such as laboratory testing or pH indicators, when determining the nature of a chemical. | 
