You stop for a cappuccino at a coffee shop and notice that the tiny white bubbles of steamed milk remain on the surface of the coffee. These

You stop for a cappuccino at a coffee shop and notice that the tiny white bubbles of steamed milk remain on the surface of the coffee. These air-filled bubbles stay where they are, rather than descending into the coffee or rising into the air, because they are:

A. more dense than the coffee but less dense than the air above thecoffee.

B. thicker than the coffee but less thick than the air above thecoffee.

C. less dense than the coffee but more dense than the air above thecoffee.

D. lighter than the cup of coffee but heavier than the column ofair above the coffee.