6. which is an opinion? a although they are sprinters, greyhounds are generally not high-energy dogs. b some rescue groups provide agility training and obedience classes for newly adopted greyhounds. c most greyhounds are to walk once a day then spend their time napping. d a greyhound in full flight is the most beautiful sight in the world.

The correct answer is D. A greyhound in full flight is the most beautiful sight in the world.

Explanation:

In language, an opinion refers to a statement that expresses personal points of view, judgment or thoughts that are subjective and therefore vary in each person. This implies, different from facts opinions are not universal and cannot be tested. Considering this, the statement that is an opinion rather than a fact is "A greyhound in full flight is the most beautiful sight in the world" because the concept of "beauty" is mainly subjective, which means this is a personal point of view but not a fact or statement that is universal or can be proven, as some people might consider the ocean, the dawn, etc are the most beautiful sight in the world.

d. cassius cannot believe that a weakling like caesar has become so great.

fond of fighting is the answer