Let
F
F
be a field of characteristic different from
2
2
and such that virtual cohomological dimension of
F
F
is
2
2
. Let
G
G
be a semisimple classical adjoint group of type
D
n
D_n
defined over
F
F
. We show that
G
(
F
)
/
R
=
0
G(F) / R = 0
, where
R
R
denotes rational equivalence on
G
(
F
)
G(F)
. The analogous result for groups of type
1
A
n
{}^1A_n
and
B
n
B_n
has been proved by Merkurjev, for groups of type
2
A
2
n
{}^2A_{2n}
by Voskresenskii-Klyachko and for general groups of type
2
A
n
{}^2A_n
and
C
n
C_n
by Kulshreshta-Parimala. Combining the main theorem of this paper with the above mentioned results, we have
G
(
F
)
/
R
G(F) / R
is trivial, for any semisimple adjoint classical group
G
G
defined over
F
F
.