Noted for its tenacity and courage,
the English bulldog, having originally been bred for the brutal sport of bull-baiting, but now is cherished as a loyal animal companion.
A) the English bulldog, having originally been bred for the brutal sport of bullbaiting, but now is cherished
No main verb
B) English bulldogs were originally bred for the brutal sport of bull-baiting, but they are now cherished
Plural "bulldogs" do not agree in number with non underlined pronoun
C) English bulldogs were originally bred to bait bulls in a brutal sport, but it is now cherished
Plural "bulldogs" do not agree in number with non underlined pronoun
D) the English bulldog was originally bred for the brutal sport of bull-baiting, but it is now cherished
Correct
E) the English bulldog, originally bred to bait bulls for a brutal sport, is now being cherished
Essential information enclosed in comma
Being is wrongly used
(D) is correct