A student adds 2 mL of acetic acid to a test tube containing 2 mL of distilled water. He then shakes the test tube well and leaves it to settle for some time. After about 5 minutes, he observes that in the test tube there is _______.
(A) a clear transparent colourless solution
(B) a clear transparent pink solution
(C) a precipitate settling at the bottom of the test tube
(D) a layer of water over the layer of acetic acid
