In the following sentence, a part of the sentence is underlined. Below are given alternatives to the underlined part, which may improve the sentence. Choose the correct alternative. In case no improvement is needed, choose the option that indicates 'No improvement'.

It turns out that cultures with a history of dairy farming and milk drinking have a much larger frequency of lactose tolerance - and its associated gene - than those who don't.

A. More larger frequency

B. Much higher frequency

C. Many higher frequencies

D. Much larger frequencies