Given a text T, and several options, according to the question posed in the text T to choose the most appropriate option from the options as the answer, please directly output the most appropriate option, do not need to output the explanation.

One disadvantage of the Herfindahl–Hirschmann Index is that the index:
Option A:is difficult to compute.
Option B:fails to reflect low barriers to entry.
Option C:fails to reflect the effect of mergers in the industry.

Answer: B