B. If $k$ numbers are chosen from 2, $, 8, \cdots, 101$ these 34 numbers, where the sum of at least two of them is 43, then the minimum value of $k$ is: $\qquad$
B. 28.

Divide the 14 numbers less than 43 into the following seven groups: $(2,41),(5,38),(8,35),(11,32)$, $(14,29),(17,26),(20,23)$.

The sum of the two numbers in each group is 43. After selecting one number from each group and then taking all numbers greater than 43, a total of 27 numbers are selected. The sum of any two of these 27 numbers is not equal to 43.

On the other hand, if 28 numbers are selected, then in the above groups, there must be one group where both numbers are selected, and their sum is 43.
In summary, the minimum value of $k$ is 28.