Final answer:
When byes are in an odd number for a knockout tournament, the number of byes in the lower half is calculated by taking half the total number of byes and subtracting one, represented by (nb - 1)/2.
Step-by-step explanation:
The correct option for calculating the number of byes in the lower half of a knockout tournament when there is an odd number of byes is (b) nb-1/2. Here, 'nb' represents the number of byes. When distributing byes in a tournament, if there is an odd number of byes, you split the total number of byes into two equal parts for the upper and lower half of the draw, with one extra bye placed in the upper half. Therefore, the lower half would have one less than half of the total number of byes, which is correctly expressed as (nb - 1)/2.