Which of the part of tongue bears cells for sour taste?

Which of the part of tongue bears cells for sour taste?A. Front
B. Back
C. Sides
D. Middle

The taste buds for “sweet” are on the tip of the tongue; the “salt” taste buds are on either side of the front of the tongue; “sour” taste buds are behind this; and “bitter” taste buds are way in the back.