Veterinary researchers at a major university veterinary hospital calculated a 99% confidence interval for the average age of horses admitted for laminitis, a foot disease that leaves the horse severely lame, as 6.3 to 7.4 years. Based on this information we conclude that:

a. We can be 100% sure that the average age of horses admitted with laminitis is between 6.3 and 7.4 years.

b. 99% of all horses admitted for laminitis are between 6.3 and 7.4 years old.

c. All of the above d. we are 99% confident that the true mean age of horses with laminitis is between 6.3 and 7.4 years old.

Answer: d. we are 99% confident that the true mean age of horses with laminitis is between 6.3 and 7.4 years old.

Step-by-step explanation:

A x% confidence interval interprets that a person can be x% sure that the true population parameter lies in it.

Given : Veterinary researchers at a major university veterinary hospital.

He calculated a 99% confidence interval for the average age of horses admitted for laminitis, a foot disease that leaves the horse severely lame, as 6.3 to 7.4 years.

Here, Population parameter = Mean age of horses with laminitis

Interpretation: We are 99% sure that the true mean age of horses with laminitis is between 6.3 and 7.4 years old.

Hence, the correct option is d. we are 99% confident that the true mean age of horses with laminitis is between 6.3 and 7.4 years old.