GMAT Sentence Correction (SC) | Re: Although the organizers of the famous English rock festival Glass Town

Although the organizers of the famous English rock festival Glass Town Berry have provided appropriate camping arrangements forfestival-goers, the number of attendants who chose to sleep in a tent over accommodation in nearby towns have amounted to a mere sum of 30,000 , a meager 10% of the total number of tickets sold.

A.the number of attendants who chose to sleep in a tent over accomodation in nearby towns have amounted to a mere sum of 30,000
B.the number of attendants, who chose to sleep