Bases release ions when diluted, are slick to the touch, and have a bitter flavour. They provide a solution of electrolyte. With this knowledge, the right response ought to be obvious.

Bases are those chemical compounds that can counteract an acid's effects. Although certain bases dissolve in water, most do not. Alkalis are bases that dissolved in water.
We shall list the physical and chemical characteristics of bases. Physical characteristics are those that our senses can recognise. These physical characteristics can be felt, seen, smelled, or touched to help us recognise them.
The following are bases' physical characteristics.
I. They have a bitter flavour.
II. They have a soapy or slick feel about them.
They become red litmus blue.
The chemical characteristics of the bases are as follows:
I. When they react with acids, they produce salt and water.
II. Bases react with metals to produce hydrogen gas.
III. Some bases transmit electricity, but only when they are watery. In solid form, they are poor conductors.
In solution, bases generate hydroxide ions.
On dilution, they release ions and generate heat.

Hence,the correct option is (D).