Miroslav Klose, with 14 goals to his credit, is the second leading goal scorer in football world cups, bettered only by Ronaldo's 15 goals.
-Look at this sentence from end to end to assess what is going on.
A) bettered only by Ronaldo's 15 goals
-This version incorrectly compares Miroslav Klose to Ronaldo's 15 goals, saying essentially, "Miroslav Klose is bettered only by Ronaldo's 15 goals."
B) bettered only by Ronaldo, who has 15 goals to his name
-This version correctly conveys that Miroslav close is bettered by Ronaldo, who has 15 goals.
C) only bettered by Ronaldo's 15 goals
-This version incorrectly compares Miroslav Klose to Ronaldo's goals.
-Also the placement of only in this version distorts the meaning. The point is not that Klose is only bettered by Ronaldo. The point is that Klose is bettered only by Ronaldo, and nobody else
D) bettered only by Ronaldo and his 15 goals
-This starts off OK, comparing Klose to Ronaldo, but then compares Klose to Ronaldo's goals.
E) only bettered by Ronaldo , having 15 goals to his name
-The placement of only before bettered distorts the meaning. The point is not that Klose is only bettered by Ronaldo. The point is that Klose is bettered only by Ronaldo, and nobody else.
-Also, in this version, the modifier, having 15 goals to his name, which is placed after a comma and in such a way as to modify the entire clause, seems to be referring to Klose rather than to Ronaldo.
So the correct answer is B.