3. Given that the sum of 5 different positive odd numbers is 85. Then the range of the largest number $M$ among these five numbers is ( ).
(A) $23 \leqslant M \leqslant 67$
(B) $19 \leqslant M \leqslant 67$
(C) $21 \leqslant M \leqslant 69$
(D) $17 \leqslant M \leqslant 69$
3. (C).

Naturally, when taking 4 positive odd numbers as $1,3,5,7$, the maximum number reaches its maximum value of 69; when the maximum odd number is $x$, and the other four numbers are $x-8, x-6, x-4, x-2$, then $x-8+x-6+x-4+x-2+x=$ 85, $x=21$. Therefore, $21 \leqslant M \leqslant 69$.