What output will the following command sequence produce?

What output will the following command sequence produce?
echo ‘1 2 3 4 5 6’ | while read a b c; do
echo result: $c $b $a;
done

A.
result: 3 4 5 6 2 1

B.
result: 1 2 3 4 5 6

C.
result: 6 5 4

D.
result: 6 5 4 3 2 1

E.
result: 3 2 1