The incorrect part of the statement is:

“sponsors of the ICC World cup tournament 'who bought' advertising time on television 'includes' 'at least' dozen international firms 'whose' names are familiar to many consumers.”

The correct version should be:

“sponsors of the ICC World cup tournament 'that bought' advertising time on television 'include' 'at least' a dozen international firms 'whose' names are familiar to many consumers.”

Here are the corrections:

"who bought" should be changed to "that bought." The word "that" is used to introduce a restrictive clause, providing essential information about the sponsors.

"includes" should be changed to "include" to agree with the plural noun “sponsors.”

"dozen" should be changed to "a dozen" to specify the quantity.

"whose" is correct and refers to possession or association.

The corrected sentence would be:

“Sponsors of the ICC World cup tournament that bought advertising time on television include at least a dozen international firms whose names are familiar to many consumers.”