Answer: NaOH
Step-by-step explanation:
The base can be defined as the chemical species which has the ability to denote electrons, always ready to accept protons.
These species released hydroxide ions in the aqueous solution. Example: hydroxide of alkaline earth metals like sodium hydroxide, calcium hydroxide.
These reacts with acid to form salt and water. Turns the red litmus blue. Hence, the correct answer is option B.